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  <title>CSS Multi-column Layout Module Level 1</title>
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  <meta content="This specification describes multi-column layouts in CSS, a style sheet language for the web. Using functionality described in the specification, content can be flowed into multiple columns with a gap and a rule between them." name="abstract">
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 <body class="h-entry">
  <div class="head">
   <p data-fill-with="logo"><a class="logo" href="https://www.w3.org/"> <img alt="W3C" height="48" src="https://www.w3.org/StyleSheets/TR/2016/logos/W3C" width="72"> </a> </p>
   <h1 class="p-name no-ref" id="title">CSS Multi-column Layout Module Level 1</h1>
   <h2 class="no-num no-toc no-ref heading settled" id="subtitle"><span class="content">Editor’s Draft, <time class="dt-updated" datetime="1970-01-01">1 January 1970</time></span></h2>
   <details>
    <summary>Specification Metadata</summary>
    <div data-fill-with="spec-metadata">
     <dl>
      <dt>This version:
      <dd><a class="u-url" href="https://drafts.csswg.org/css-multicol/">https://drafts.csswg.org/css-multicol/</a>
      <dt>Latest published version:
      <dd><a href="https://www.w3.org/TR/css-multicol-1/">https://www.w3.org/TR/css-multicol-1/</a>
      <dt>Previous Versions:
      <dd><a href="https://www.w3.org/TR/2018/WD-css-multicol-1-20180528/" rel="prev">https://www.w3.org/TR/2018/WD-css-multicol-1-20180528/</a>
      <dd><a href="https://www.w3.org/TR/2017/WD-css-multicol-1-20171005/" rel="prev">https://www.w3.org/TR/2017/WD-css-multicol-1-20171005/</a>
      <dd><a href="https://www.w3.org/TR/2011/CR-css3-multicol-20110412/" rel="prev">https://www.w3.org/TR/2011/CR-css3-multicol-20110412/</a>
      <dd><a href="https://www.w3.org/TR/2009/CR-css3-multicol-20091217/" rel="prev">https://www.w3.org/TR/2009/CR-css3-multicol-20091217/</a>
      <dd><a href="https://www.w3.org/TR/2009/WD-css3-multicol-20090630/" rel="prev">https://www.w3.org/TR/2009/WD-css3-multicol-20090630/</a>
      <dd><a href="https://www.w3.org/TR/2007/WD-css3-multicol-20070606/" rel="prev">https://www.w3.org/TR/2007/WD-css3-multicol-20070606/</a>
      <dd><a href="https://www.w3.org/TR/2005/WD-css3-multicol-20051215/" rel="prev">https://www.w3.org/TR/2005/WD-css3-multicol-20051215/</a>
      <dd><a href="https://www.w3.org/TR/2001/WD-css3-multicol-20010118/" rel="prev">https://www.w3.org/TR/2001/WD-css3-multicol-20010118/</a>
      <dd><a href="http://www.w3.org/1999/06/WD-css3-multicol-19990623" rel="prev">http://www.w3.org/1999/06/WD-css3-multicol-19990623</a>
      <dt>Test Suite:
      <dd><a href="http://test.csswg.org/suites/css-multicol-1_dev/nightly-unstable/">http://test.csswg.org/suites/css-multicol-1_dev/nightly-unstable/</a>
      <dt>Issue Tracking:
      <dd><a href="https://drafts.csswg.org/css-multicol-1/issues">Disposition of Comments</a>
      <dd><a href="https://github.com/w3c/csswg-drafts/labels/css-multicol-1">GitHub Issues</a>
      <dt class="editor">Editors:
      <dd class="editor p-author h-card vcard" data-editor-id="9796"><a class="p-name fn u-email email" href="mailto:howcome@opera.com">Håkon Wium Lie</a> (<span class="p-org org">Opera Software</span>)
      <dd class="editor p-author h-card vcard" data-editor-id="43241"><a class="p-name fn u-url url" href="https://florian.rivoal.net">Florian Rivoal</a> (<span class="p-org org">On behalf of Bloomberg</span>)
      <dd class="editor p-author h-card vcard" data-editor-id="81117"><a class="p-name fn u-url url" href="https://rachelandrew.co.uk">Rachel Andrew</a> (<span class="p-org org">Fronteers</span>)
      <dt>Suggest an Edit for this Spec:
      <dd><a href="https://github.com/w3c/csswg-drafts/blob/master/css-multicol-1/Overview.bs">GitHub Editor</a>
     </dl>
    </div>
   </details>
   <div data-fill-with="warning"></div>
   <p class="copyright" data-fill-with="copyright"><a href="https://www.w3.org/Consortium/Legal/ipr-notice#Copyright">Copyright</a> © 1970 <a href="https://www.w3.org/"><abbr title="World Wide Web Consortium">W3C</abbr></a><sup>®</sup> (<a href="https://www.csail.mit.edu/"><abbr title="Massachusetts Institute of Technology">MIT</abbr></a>, <a href="https://www.ercim.eu/"><abbr title="European Research Consortium for Informatics and Mathematics">ERCIM</abbr></a>, <a href="https://www.keio.ac.jp/">Keio</a>, <a href="https://ev.buaa.edu.cn/">Beihang</a>). W3C <a href="https://www.w3.org/Consortium/Legal/ipr-notice#Legal_Disclaimer">liability</a>, <a href="https://www.w3.org/Consortium/Legal/ipr-notice#W3C_Trademarks">trademark</a> and <a href="https://www.w3.org/Consortium/Legal/2015/copyright-software-and-document">permissive document license</a> rules apply. </p>
   <hr title="Separator for header">
  </div>
  <div class="p-summary" data-fill-with="abstract">
   <h2 class="no-num no-toc no-ref heading settled" id="abstract"><span class="content">Abstract</span></h2>
   <p>This specification describes multi-column layouts in CSS, a style sheet language for the web. Using functionality described in the specification, content can be flowed into multiple columns with a gap and a rule between them.</p>
    <a href="https://www.w3.org/TR/CSS/">CSS</a> is a language for describing the rendering of structured documents
(such as HTML and XML)
on screen, on paper, etc. 
  </div>
  <h2 class="no-num no-toc no-ref heading settled" id="status"><span class="content">Status of this document</span></h2>
  <div data-fill-with="status">
   <p> This is a public copy of the editors’ draft.
	It is provided for discussion only and may change at any moment.
	Its publication here does not imply endorsement of its contents by W3C.
	Don’t cite this document other than as work in progress. </p>
   <p> <a href="https://github.com/w3c/csswg-drafts/issues">GitHub Issues</a> are preferred for discussion of this specification.
	When filing an issue, please put the text “css-multicol” in the title,
	preferably like this:
	“[css-multicol] <i data-lt>…summary of comment…</i>”.
	All issues and comments are <a href="https://lists.w3.org/Archives/Public/public-css-archive/">archived</a>,
	and there is also a <a href="https://lists.w3.org/Archives/Public/www-style/">historical archive</a>. </p>
   <p> This document was produced by the <a href="https://www.w3.org/Style/CSS/">CSS Working Group</a>. </p>
   <p> This document was produced by a group operating under
	the <a href="https://www.w3.org/Consortium/Patent-Policy/">W3C Patent Policy</a>.
	W3C maintains a <a href="https://www.w3.org/2004/01/pp-impl/32061/status" rel="disclosure">public list of any patent disclosures</a> made in connection with the deliverables of the group;
	that page also includes instructions for disclosing a patent.
	An individual who has actual knowledge of a patent which the individual believes contains <a href="https://www.w3.org/Consortium/Patent-Policy/#def-essential">Essential Claim(s)</a> must disclose the information in accordance with <a href="https://www.w3.org/Consortium/Patent-Policy/#sec-Disclosure">section 6 of the W3C Patent Policy</a>. </p>
   <p> This document is governed by the <a href="https://www.w3.org/2019/Process-20190301/" id="w3c_process_revision">1 March 2019 W3C Process Document</a>. </p>
   <p></p>
  </div>
  <div data-fill-with="at-risk"></div>
  <nav data-fill-with="table-of-contents" id="toc">
   <h2 class="no-num no-toc no-ref" id="contents">Table of Contents</h2>
   <ol class="toc" role="directory">
    <li><a href="#introduction"><span class="secno">1</span> <span class="content"> Introduction</span></a>
    <li><a href="#the-multi-column-model"><span class="secno">2</span> <span class="content"> The Multi-Column Model</span></a>
    <li>
     <a href="#the-number-and-width-of-columns"><span class="secno">3</span> <span class="content"> The Number and Width of Columns</span></a>
     <ol class="toc">
      <li><a href="#cw"><span class="secno">3.1</span> <span class="content">The Inline Size of Columns: the <span class="property">column-width</span> property</span></a>
      <li><a href="#cc"><span class="secno">3.2</span> <span class="content">The Number of Columns: the <span class="property">column-count</span> property</span></a>
      <li><a href="#columns"><span class="secno">3.3</span> <span class="content">The <span class="property">column-width</span> and <span class="property">column-count</span> Shorthand: The <span class="property">columns</span> Property</span></a>
      <li><a href="#pseudo-algorithm"><span class="secno">3.4</span> <span class="content">The Pseudo-algorithm</span></a>
      <li><a href="#stacking-context"><span class="secno">3.5</span> <span class="content"> Stacking Context</span></a>
     </ol>
    <li>
     <a href="#column-gaps-and-rules"><span class="secno">4</span> <span class="content">Column Gaps and Rules</span></a>
     <ol class="toc">
      <li><a href="#cg"><span class="secno">4.1</span> <span class="content">Gutters Between Columns: the <span class="property">column-gap</span> property</span></a>
      <li><a href="#crc"><span class="secno">4.2</span> <span class="content">The Color of Column Rules: the <span class="property">column-rule-color</span> property</span></a>
      <li><a href="#crs"><span class="secno">4.3</span> <span class="content">The Style Of Column Rules: the <span class="property">column-rule-style</span> property</span></a>
      <li><a href="#crw"><span class="secno">4.4</span> <span class="content">The Width Of Column Rules: the <span class="property">column-rule-width</span> property</span></a>
      <li><a href="#cr"><span class="secno">4.5</span> <span class="content">Column Rule Shorthand: the <span class="property">column-rule</span> property</span></a>
     </ol>
    <li>
     <a href="#column-breaks"><span class="secno">5</span> <span class="content"> Column Breaks</span></a>
     <ol class="toc">
      <li><a href="#break-before-break-after-break-inside"><span class="secno">5.1</span> <span class="content">Controlling Fragmentation: the <span class="property">break-before</span>, <span class="property">break-after</span>, <span class="property">break-inside</span> properties</span></a>
     </ol>
    <li>
     <a href="#spanning-columns"><span class="secno">6</span> <span class="content"> Spanning Columns</span></a>
     <ol class="toc">
      <li><a href="#column-span"><span class="secno">6.1</span> <span class="content">Spanning An Element Across Columns: the <span class="property">column-span</span> property</span></a>
     </ol>
    <li>
     <a href="#filling-columns"><span class="secno">7</span> <span class="content"> Filling Columns</span></a>
     <ol class="toc">
      <li><a href="#cf"><span class="secno">7.1</span> <span class="content">Column Balancing: the <span class="property">column-fill</span> property</span></a>
     </ol>
    <li>
     <a href="#overflow"><span class="secno">8</span> <span class="content"> Overflow</span></a>
     <ol class="toc">
      <li><a href="#overflow-inside-multicol-elements"><span class="secno">8.1</span> <span class="content"> Overflow Inside Multicol Containers</span></a>
      <li><a href="#pagination-and-overflow-outside-multicol"><span class="secno">8.2</span> <span class="content"> Pagination and Overflow Outside Multicol Containers</span></a>
     </ol>
    <li>
     <a href="#changes"><span class="secno"></span> <span class="content">Appendix B. Changes</span></a>
     <ol class="toc">
      <li><a href="#changes-from-20180528"><span class="secno"></span> <span class="content">Changes from the <span>Working Draft (WD) of 28 May 2018</span></span></a>
      <li><a href="#changes-from-20171005"><span class="secno"></span> <span class="content">Changes from the <span>Working Draft (WD) of 5 October 2017</span></span></a>
      <li><a href="#changes-from-20110412"><span class="secno"></span> <span class="content">Changes from the <span>Candidate Recommendation (CR) of 12 April 2011</span>.</span></a>
     </ol>
    <li><a href="#acknowledgments"><span class="secno"></span> <span class="content"> Acknowledgments</span></a>
    <li>
     <a href="#conformance"><span class="secno"></span> <span class="content"> Conformance</span></a>
     <ol class="toc">
      <li><a href="#document-conventions"><span class="secno"></span> <span class="content"> Document conventions</span></a>
      <li><a href="#conform-classes"><span class="secno"></span> <span class="content"> Conformance classes</span></a>
      <li>
       <a href="#conform-responsible"><span class="secno"></span> <span class="content"> Requirements for Responsible Implementation of CSS</span></a>
       <ol class="toc">
        <li><a href="#conform-partial"><span class="secno"></span> <span class="content"> Partial Implementations</span></a>
        <li><a href="#conform-future-proofing"><span class="secno"></span> <span class="content"> Implementations of Unstable and Proprietary Features</span></a>
        <li><a href="#conform-testing"><span class="secno"></span> <span class="content"> Implementations of CR-level Features</span></a>
       </ol>
     </ol>
    <li>
     <a href="#index"><span class="secno"></span> <span class="content">Index</span></a>
     <ol class="toc">
      <li><a href="#index-defined-here"><span class="secno"></span> <span class="content">Terms defined by this specification</span></a>
      <li><a href="#index-defined-elsewhere"><span class="secno"></span> <span class="content">Terms defined by reference</span></a>
     </ol>
    <li>
     <a href="#references"><span class="secno"></span> <span class="content">References</span></a>
     <ol class="toc">
      <li><a href="#normative"><span class="secno"></span> <span class="content">Normative References</span></a>
      <li><a href="#informative"><span class="secno"></span> <span class="content">Informative References</span></a>
     </ol>
    <li><a href="#property-index"><span class="secno"></span> <span class="content">Property Index</span></a>
    <li><a href="#issues-index"><span class="secno"></span> <span class="content">Issues Index</span></a>
   </ol>
  </nav>
  <main>
   <h2 class="heading settled" data-level="1" id="introduction"><span class="secno">1. </span><span class="content"> Introduction</span><a class="self-link" href="#introduction"></a></h2>
   <p>(This section is not normative.)</p>
   <p>This module describes <dfn class="dfn-paneled" data-dfn-type="dfn" data-export id="multi-column-layout">multi-column layout</dfn> in CSS.
	By using functionality described in this document, 
	style sheets can declare that the content of an element 
	is to be laid out in multiple columns.</p>
   <p>Other layout methods in CSS,
	when applied to a parent element, 
	change the display properties of the direct children. 
	For example if a three column grid layout is created, 
	the direct children of the <a data-link-type="dfn" href="https://drafts.csswg.org/css-grid-1/#grid-container" id="ref-for-grid-container">grid container</a> become <a data-link-type="dfn" href="https://drafts.csswg.org/css-grid-1/#grid-item" id="ref-for-grid-item">grid items</a> and are placed into the column tracks, 
	one element per cell with additional rows created as needed.</p>
   <p>The child elements of a <a data-link-type="dfn" href="#multi-column-container" id="ref-for-multi-column-container">multi-column container</a> however continue in normal flow,
	that flow is arranged into a number of columns. 
	These columns have a flexible inline size, 
	and therefore respond to available space 
	by changing the size or number of columns displayed.</p>
   <p>Multi-column layouts are easy to describe in CSS.
	Here is a simple example:</p>
   <div class="example" id="example-90f03bde">
    <a class="self-link" href="#example-90f03bde"></a> 
<pre class="highlight"><c- f>body </c-><c- p>{</c-> <c- k>column-width</c-><c- p>:</c-> <c- m>12</c-><c- l>em</c-> <c- p>}</c-></pre>
    <p>In this example, the <code class="html">body</code> element is
		set to have columns at least <span class="css">12em</span> wide. The exact number of
		columns will depend on the available space.</p>
   </div>
   <p>The number of columns can also be set explicitly in the style sheet:</p>
   <div class="example" id="example-7e147b89">
    <a class="self-link" href="#example-7e147b89"></a> 
<pre class="highlight"><c- f>body </c-><c- p>{</c-> <c- k>column-count</c-><c- p>:</c-> <c- m>2</c-> <c- p>}</c-></pre>
    <p>In this case, the number of columns is fixed
		and the column widths will vary depending on the available width.</p>
   </div>
   <p>The shorthand <a class="property" data-link-type="propdesc" href="#propdef-columns" id="ref-for-propdef-columns">columns</a> property can be used to set either,
	or both, properties in one declaration.</p>
   <div class="example" id="example-6c6d6717">
    <a class="self-link" href="#example-6c6d6717"></a> In these examples, the number of columns, the width of columns, and
		both the number and width are set, respectively: 
<pre class="highlight"><c- f>body </c-><c- p>{</c-> <c- k>columns</c-><c- p>:</c-> <c- m>2</c-> <c- p>}</c->
<c- f>body </c-><c- p>{</c-> <c- k>columns</c-><c- p>:</c-> <c- m>12</c-><c- l>em</c-> <c- p>}</c->
<c- f>body </c-><c- p>{</c-> <c- k>columns</c-><c- p>:</c-> <c- m>2</c-> <c- m>12</c-><c- l>em</c-> <c- p>}</c->
</pre>
   </div>
   <p>Another group of properties introduced in this module describe
	gaps and rules between columns.</p>
   <div class="example" id="example-21b75f3b">
    <a class="self-link" href="#example-21b75f3b"></a> 
<pre class="highlight"><c- f>body </c-><c- p>{</c->
  <c- k>column-gap</c-><c- p>:</c-> <c- m>1</c-><c- l>em</c-><c- p>;</c->
  <c- k>column-rule</c-><c- p>:</c-> thin solid black<c- p>;</c->
<c- p>}</c->
</pre>
    <p>The first declaration in the example above sets the gap
		between two adjacent columns to be 1em. 
		Column gaps are similar to padding areas.
		In the middle of the gap there will be a rule 
		which is described by the <a class="property" data-link-type="propdesc" href="#propdef-column-rule" id="ref-for-propdef-column-rule">column-rule</a> property.</p>
   </div>
   <p>The values of the <a class="property" data-link-type="propdesc" href="#propdef-column-rule" id="ref-for-propdef-column-rule①">column-rule</a> property are similar to those of the CSS <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-backgrounds-3/#propdef-border" id="ref-for-propdef-border">border</a> properties.
	Like <span class="property" id="ref-for-propdef-border①">border</span>, <span class="property" id="ref-for-propdef-column-rule②">column-rule</span> is a shorthand property.</p>
   <div class="example" id="example-968144c8">
    <a class="self-link" href="#example-968144c8"></a> In this example, the shorthand <a class="property" data-link-type="propdesc" href="#propdef-column-rule" id="ref-for-propdef-column-rule③">column-rule</a> declaration from the
		above example has been expanded: 
<pre class="highlight"><c- f>body </c-><c- p>{</c->
  <c- k>column-gap</c-><c- p>:</c-> <c- m>1</c-><c- l>em</c-><c- p>;</c->
  <c- k>column-rule-width</c-><c- p>:</c-> thin<c- p>;</c->
  <c- k>column-rule-style</c-><c- p>:</c-> solid<c- p>;</c->
  <c- k>column-rule-color</c-><c- p>:</c-> black<c- p>;</c->
<c- p>}</c->
</pre>
   </div>
   <p>The <a class="property" data-link-type="propdesc" href="#propdef-column-fill" id="ref-for-propdef-column-fill">column-fill</a> and <a class="property" data-link-type="propdesc" href="#propdef-column-span" id="ref-for-propdef-column-span">column-span</a> properties
	give style sheets a wider range of visual expressions in multi-column layouts.</p>
   <div class="example" id="example-8550a53a">
    <a class="self-link" href="#example-8550a53a"></a> In this example, columns are set to be balanced, 
		i.e., to have approximately the same length. 
		Also, <code>h2</code> elements are set to span across all columns. 
<pre class="highlight"><c- f>div </c-><c- p>{</c-> <c- k>column-fill</c-><c- p>:</c-> balance <c- p>}</c->
<c- f>h2 </c-><c- p>{</c-> <c- k>column-span</c-><c- p>:</c-> all <c- p>}</c->
</pre>
   </div>
   <p>This specification introduces ten new properties,
	all of which are used in the examples above.</p>
   <p>If all column properties have their initial value,
	the layout of an element will be identical 
	to a multi-column layout with only one column.</p>
   <div class="example" id="example-47371199">
    <a class="self-link" href="#example-47371199"></a> <a data-link-type="dfn" href="#column-gap" id="ref-for-column-gap">Column gaps</a> (diagonal hatching) and <a data-link-type="dfn" href="#column-rule" id="ref-for-column-rule">column rules</a> are shown in this sample rendition of a multi-column container 
		with padding (cross hatching). 
		The hatched areas are present for illustrational purposes only. 
		In actual implementations these areas will be determined by the background, 
		the second image shows a rendering of a <a data-link-type="dfn" href="#multi-column-container" id="ref-for-multi-column-container①">multi-column container</a> with column-rules. 
    <figure>
      <img alt="a diagram showing the various parts of multi-column layout" src="images/initial-example.svg"> <img alt="key to the conventions used to display invisible parts of diagram" src="images/invisible-elements.svg"> 
     <figcaption>A multi-column layout with the non-visible column-span and padding inside the multicol container highlighted.</figcaption>
    </figure>
    <figure>
      <img alt="a diagram showing the various parts of multi-column layout" src="images/initial-example-b.svg"> 
     <figcaption>The same layout as in the first image, as it would be displayed by an implementation.</figcaption>
    </figure>
   </div>
   <h2 class="heading settled" data-level="2" id="the-multi-column-model"><span class="secno">2. </span><span class="content"> The Multi-Column Model</span><a class="self-link" href="#the-multi-column-model"></a></h2>
   <p>An element whose <a class="property" data-link-type="propdesc" href="#propdef-column-width" id="ref-for-propdef-column-width">column-width</a> or <a class="property" data-link-type="propdesc" href="#propdef-column-count" id="ref-for-propdef-column-count">column-count</a> property is not <a class="css" data-link-type="maybe" href="#valdef-column-width-auto" id="ref-for-valdef-column-width-auto">auto</a> establishes a <dfn class="dfn-paneled" data-dfn-type="dfn" data-export data-lt="multi-column container|multicol container" id="multi-column-container">multi-column container<span id="multi-column-element"></span></dfn> (or <i>multicol container</i> for short),
	and therefore acts as a container for <a data-link-type="dfn" href="#multi-column-layout" id="ref-for-multi-column-layout">multi-column layout</a>.</p>
   <p>In the traditional CSS box model,
	the content of an element is
	flowed into the content box of the corresponding element. 
	Multi-column layout introduces a <a data-link-type="dfn" href="https://drafts.csswg.org/css-break-4/#fragmentation-context" id="ref-for-fragmentation-context">fragmentation context</a> formed of <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#anonymous" id="ref-for-anonymous">anonymous</a> <a data-link-type="dfn" href="https://drafts.csswg.org/css-break-4/#fragmentation-container" id="ref-for-fragmentation-container">fragmentation containers</a> called <dfn class="dfn-paneled" data-dfn-type="dfn" data-export data-local-lt="column" data-lt="column box" id="column-box">column boxes</dfn> (or <i>columns</i> for short).
	These <a data-link-type="dfn" href="#column-box" id="ref-for-column-box">column boxes</a> establish
	an independent <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#block-formatting-context" id="ref-for-block-formatting-context">block formatting context</a> into which the multi-column container’s content flows,
	and form the <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#containing-block" id="ref-for-containing-block">containing block</a> for its non-positioned children.</p>
   <div class="example" id="example-5cbb5b6f">
    <a class="self-link" href="#example-5cbb5b6f"></a> In this example, the width of the image is set with these rules: 
<pre class="highlight"><c- f>img </c-><c- p>{</c-> 
  <c- k>display</c-><c- p>:</c-> block<c- p>;</c-> 
  <c- k>width</c-><c- p>:</c-> <c- m>100</c-><c- l>%</c-><c- p>;</c-> 
<c- p>}</c->
</pre>
    <p>Given that the column box creates a new <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#block-formatting-context" id="ref-for-block-formatting-context①">block formatting context</a>,
		the <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css2/visudet.html#propdef-width" id="ref-for-propdef-width">width</a> is calculated relative to the column box. 
		Therefore the image will not overflow the column box:</p>
    <figure>
      <img alt="an image contained inside a column box" src="images/image-inside-column.svg"> 
     <figcaption>The image is constrained by the column box that it is displayed in.</figcaption>
    </figure>
   </div>
   <div class="example" id="example-88e557c8">
    <a class="self-link" href="#example-88e557c8"></a> Given that the column box creates a new <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#block-formatting-context" id="ref-for-block-formatting-context②">block formatting context</a>, a top margin set on the first child element of a multicol container will not collapse with the margins of the multicol container. 
    <figure>
      <img alt="The first paragraph has a &apos;margin-top&apos; of <fake-maybe-placeholder bs-autolink-syntax=&apos;&apos;&apos;1em&apos;&apos;&apos;>1em</fake-maybe-placeholder>, which appears before the text." src="images/margins-do-not-collapse.svg"> 
     <figcaption>The margin above the first paragraph has not collapsed, leaving a <span class="css">1em</span> margin above the first line in the multicol container.</figcaption>
    </figure>
   </div>
   <p>Floats that appear inside multi-column layouts are positioned with
	regard to the <a data-link-type="dfn" href="#column-box" id="ref-for-column-box①">column box</a> where the float appears.</p>
   <div class="example" id="example-3dc32251">
    <a class="self-link" href="#example-3dc32251"></a> In this example, this CSS fragment describes the presentation of the image: 
<pre class="highlight"><c- f>img </c-><c- p>{</c-> 
  <c- k>display</c-><c- p>:</c-> block<c- p>;</c-> 
  <c- k>float</c-><c- p>:</c-> right<c- p>;</c->
<c- p>}</c->
</pre>
    <p>In the HTML, the image appears after the sentence ending, "the leg of a chicken".</p>
    <figure>
      <img alt="an image floated and contained inside a column box" src="images/image-floated-in-column.svg"> 
     <figcaption>The image is floated inside the column box it appears in.</figcaption>
    </figure>
   </div>
   <p>Content overflowing a <a data-link-type="dfn" href="#column-box" id="ref-for-column-box②">column box</a> in the <a data-link-type="dfn" href="https://drafts.csswg.org/css-writing-modes-4/#block-axis" id="ref-for-block-axis">block axis</a> <a data-link-type="dfn" href="https://drafts.csswg.org/css-break-4/#fragment" id="ref-for-fragment">fragments</a> and continues in the next <span id="ref-for-column-box③">column box</span>.</p>
   <p class="note" role="note"><span>Note:</span> Column boxes, which are <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#anonymous" id="ref-for-anonymous①">anonymous boxes</a>,
	do not become the containing block
	for <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#absolutely-positioned" id="ref-for-absolutely-positioned">absolutely positioned boxes</a>.
	The <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-position-3/#propdef-position" id="ref-for-propdef-position">position</a> property, which establishes a containing block for such boxes,
	applies to the <a data-link-type="dfn" href="#multi-column-container" id="ref-for-multi-column-container②">multicol container</a>, it being the <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#principal-box" id="ref-for-principal-box">principal box</a>.</p>
   <div class="example" id="example-aaa86638">
    <a class="self-link" href="#example-aaa86638"></a> In this example, the <a data-link-type="dfn" href="#multi-column-container" id="ref-for-multi-column-container③">multi-column container</a> has <a class="css" data-link-type="propdesc" href="https://drafts.csswg.org/css-position-3/#propdef-position" id="ref-for-propdef-position①">position: relative</a> thus becoming the containing block. 
		The image is a direct child of the <span id="ref-for-multi-column-container④">multi-column container</span> and has <span class="css" id="ref-for-propdef-position②">position: absolute</span>. 
		It takes positioning from the <span id="ref-for-multi-column-container⑤">multi-column container</span> and not from the <a data-link-type="dfn" href="#column-box" id="ref-for-column-box④">column box</a>. 
<pre class="highlight"><c- f>.container </c-><c- p>{</c->
  <c- k>position</c-><c- p>:</c-> relative<c- p>;</c->
  <c- k>column-count</c-><c- p>:</c-> <c- m>3</c-><c- p>;</c->
<c- p>}</c->
<c- f>img </c-><c- p>{</c->
  <c- k>position</c-><c- p>:</c-> absolute<c- p>;</c->
  <c- k>top</c-><c- p>:</c-> <c- m>20</c-><c- l>px</c-><c- p>;</c->
  <c- k>left</c-><c- p>:</c-> <c- m>40</c-><c- l>px</c-><c- p>;</c->
<c- p>}</c->
</pre>
    <figure>
      <img alt="The absolutely positioned image is positioned by reference to the [=multi-column container=] not the [=column box=]." src="images/column-not-containing-block.svg"> 
     <figcaption>The figure demonstrates that the absolutely positioned image is positioned by reference to the multicol container and not the column box.</figcaption>
    </figure>
   </div>
   <p>The column boxes are ordered
	in the <a data-link-type="dfn" href="https://drafts.csswg.org/css-writing-modes-4/#inline-base-direction" id="ref-for-inline-base-direction">inline base direction</a> of the multicol container
	and arranged into <dfn class="dfn-paneled" data-dfn-type="dfn" data-lt="multi-column line | multi-col line | multicol line" data-noexport id="multi-column-line">multicol lines</dfn>.
    The <dfn data-dfn-type="dfn" data-export id="column-width">column width<a class="self-link" href="#column-width"></a></dfn> is the length of the column box in the inline direction.
	The <dfn data-dfn-type="dfn" data-export id="column-height">column height<a class="self-link" href="#column-height"></a></dfn> is the length of the column box in the block direction.
	All column boxes in a line have the same column width,
	and all column boxes in a line have the same column height.</p>
   <p>Within each <a data-link-type="dfn" href="#multi-column-line" id="ref-for-multi-column-line">multicol line</a> in the multi-column container,
	adjacent column boxes are separated by a <dfn class="dfn-paneled" data-dfn-type="dfn" data-noexport id="column-gap">column gap</dfn>,
	which may contain a <dfn class="dfn-paneled" data-dfn-type="dfn" data-noexport id="column-rule">column rule</dfn>.
	All column gaps in the same multi-column container are equal.
	All column rules in the same multi-column container are also equal, if they appear;
	column rules only appear between columns that both have content.</p>
   <p>In the simplest case a multicol container will contain only one line
	of columns, and the height of each column will be equivalent to the
	used height of the multi-column container’s content box.
	However, <a data-link-type="dfn" href="https://drafts.csswg.org/css-break-4/#fragmentation" id="ref-for-fragmentation">fragmentation</a> or <a data-link-type="dfn" href="#spanner" id="ref-for-spanner">spanners</a> can split the content of the <a data-link-type="dfn" href="#multi-column-container" id="ref-for-multi-column-container⑥">multi-column container</a> into multiple <a data-link-type="dfn" href="#multi-column-line" id="ref-for-multi-column-line①">multicol lines</a>.</p>
   <p>If the multi-column container is paginated, the height of each column is
	constrained by the page and the content continues in a new line of
	column boxes on the next page; a column box never splits across pages.</p>
   <p>The same effect occurs when a <i>spanning element</i> divides the
	multi-column container: the columns before the spanning element are
	balanced and shortened to fit their content. Content after the
	spanning element then flows into a new, subsequent line of column boxes.</p>
   <div class="example" id="example-c2c3431f">
    <a class="self-link" href="#example-c2c3431f"></a> 
    <figure>
      <img alt="a diagram showing a spanning element causing the shortened columns above the element with text continuing in new columns below" src="images/simple-span-example.svg"> 
     <figcaption>A demonstration of how the spanning element divides the multicol container.</figcaption>
    </figure>
   </div>
   <p>A <a data-link-type="dfn" href="#multi-column-container" id="ref-for-multi-column-container⑦">multi-column container</a> therefore is a regular <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#block-container" id="ref-for-block-container">block container</a> that establishes a new <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#independent-formatting-context" id="ref-for-independent-formatting-context">independent formatting context</a> whose contents consist of a series of <a data-link-type="dfn" href="#multi-column-line" id="ref-for-multi-column-line②">multicol lines</a> and multicol spanners.
	Each <span id="ref-for-multi-column-line③">multi-column line</span> acts as a <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#block-level-box" id="ref-for-block-level-box">block-level box</a> that establishes a <dfn class="dfn-paneled" data-dfn-type="dfn" data-noexport id="multi-column-formatting-context">multi-column formatting context</dfn> for its <a data-link-type="dfn" href="#column-box" id="ref-for-column-box⑤">column boxes</a>;
	and each <a data-link-type="dfn" href="#spanner" id="ref-for-spanner①">spanner</a> acts as a <span id="ref-for-block-level-box①">block-level box</span> that establishes an <span id="ref-for-independent-formatting-context①">independent formatting context</span> with its type depending on its <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-display-3/#propdef-display" id="ref-for-propdef-display">display</a> value as usual.</p>
   <p>Nested multi-column containers are allowed,
	but there may be implementation-specific limits.</p>
   <p class="note" role="note"><span>Note:</span> It is not possible to set properties/values on column boxes.
	For example, the background of a certain column box cannot be set 
	and a column box has no concept of padding, margin or borders. 
	Future specifications may add additional functionality. 
	For example, columns of different widths and different backgrounds may be supported.</p>
   <p class="note" role="note"><span>Note:</span> Multicol containers with column heights larger than the viewport may pose accessibility issues.</p>
   <h2 class="heading settled" data-level="3" id="the-number-and-width-of-columns"><span class="secno">3. </span><span class="content"> The Number and Width of Columns</span><a class="self-link" href="#the-number-and-width-of-columns"></a></h2>
   <p>Finding the number and width of columns is fundamental when laying out multi-column content.
	These properties are used to set the number and width of columns:</p>
   <ul>
    <li><a class="property" data-link-type="propdesc" href="#propdef-column-count" id="ref-for-propdef-column-count①">column-count</a>
    <li><a class="property" data-link-type="propdesc" href="#propdef-column-width" id="ref-for-propdef-column-width①">column-width</a>
   </ul>
   <p>A third property, <a class="property" data-link-type="propdesc" href="#propdef-columns" id="ref-for-propdef-columns①">columns</a>,
	is a shorthand property which sets both <a class="property" data-link-type="propdesc" href="#propdef-column-width" id="ref-for-propdef-column-width②">column-width</a> and <a class="property" data-link-type="propdesc" href="#propdef-column-count" id="ref-for-propdef-column-count②">column-count</a>.</p>
   <p>Other factors, such as explicit column breaks, content, and height constraints,
	may influence the actual number and width of columns.</p>
   <h3 class="heading settled" data-level="3.1" id="cw"><span class="secno">3.1. </span><span class="content">The Inline Size of Columns: the <a class="property" data-link-type="propdesc" href="#propdef-column-width" id="ref-for-propdef-column-width③">column-width</a> property</span><a class="self-link" href="#cw"></a></h3>
   <table class="def propdef" data-link-for-hint="column-width">
    <tbody>
     <tr>
      <th>Name:
      <td><dfn class="dfn-paneled css" data-dfn-type="property" data-export id="propdef-column-width">column-width</dfn>
     <tr class="value">
      <th><a href="https://drafts.csswg.org/css-values/#value-defs">Value:</a>
      <td class="prod">auto <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-4/#comb-one" id="ref-for-comb-one">|</a> <a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-3/#length-value" id="ref-for-length-value" title="Expands to: em | vb | ch | cm | vh | vi | in | ex | vw | ic | pt | px | lh | pc | rem | rlh | vmax | advance measure | vmin | mm | cap | q">&lt;length></a> 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#initial-values">Initial:</a>
      <td>auto 
     <tr>
      <th>Applies to:
      <td><a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#block-container" id="ref-for-block-container①">block containers</a> except <a data-link-type="dfn" href="https://drafts.csswg.org/css-tables-3/#table-wrapper-box" id="ref-for-table-wrapper-box">table wrapper boxes</a> 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#inherited-property">Inherited:</a>
      <td>no 
     <tr>
      <th><a href="https://drafts.csswg.org/css-values/#percentages">Percentages:</a>
      <td>N/A 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#computed">Computed value:</a>
      <td>the keyword <a class="css" data-link-type="maybe" href="#valdef-column-width-auto" id="ref-for-valdef-column-width-auto①">auto</a> or an absolute length 
     <tr>
      <th>Canonical order:
      <td>per grammar 
     <tr>
      <th><a href="https://drafts.csswg.org/web-animations/#animation-type">Animation type:</a>
      <td>by computed value type 
   </table>
   <p>This property describes the width of columns in multicol containers.</p>
   <dl>
    <dt><dfn class="dfn-paneled css" data-dfn-for="column-width" data-dfn-type="value" data-export id="valdef-column-width-auto">auto</dfn>
    <dd> means that the column width will be determined by other properties
			(e.g., <a class="property" data-link-type="propdesc" href="#propdef-column-count" id="ref-for-propdef-column-count③">column-count</a>, if it has a non-auto value). 
    <dt><dfn class="css" data-dfn-for="column-width" data-dfn-type="value" data-export id="valdef-column-width-length"><a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-3/#length-value" id="ref-for-length-value①" title="Expands to: em | vb | ch | cm | vh | vi | in | ex | vw | ic | pt | px | lh | pc | rem | rlh | vmax | advance measure | vmin | mm | cap | q">&lt;length></a><a class="self-link" href="#valdef-column-width-length"></a></dfn>
    <dd> describes the optimal column width. 
			The actual column width may be wider (to fill the available space), 
			or narrower (only if the available space is smaller than the specified column width). 
			Negative values are not allowed. 
			Used values will be clamped to a minimum of <span class="css">1px</span>. 
   </dl>
   <div class="example" id="example-f5259b18">
    <a class="self-link" href="#example-f5259b18"></a> For example, consider this style sheet: 
<pre class="highlight"><c- f>div </c-><c- p>{</c->
  <c- k>width</c-><c- p>:</c-> <c- m>100</c-><c- l>px</c-><c- p>;</c->
  <c- k>column-width</c-><c- p>:</c-> <c- m>45</c-><c- l>px</c-><c- p>;</c->
  <c- k>column-gap</c-><c- p>:</c-> <c- m>0</c-><c- p>;</c->
  <c- k>column-rule</c-><c- p>:</c-> none<c- p>;</c->
<c- p>}</c->
</pre>
    <p>There is room for two <span class="css">45px</span> wide columns inside the <span class="css">100px</span> wide element.
		In order to fill the available space 
		the actual column width will be increased to <span class="css">50px</span>.</p>
   </div>
   <div class="example" id="example-ea5c2499">
    <a class="self-link" href="#example-ea5c2499"></a> Also, consider this style sheet: 
<pre class="highlight"><c- f>div </c-><c- p>{</c->
  <c- k>width</c-><c- p>:</c-> <c- m>40</c-><c- l>px</c-><c- p>;</c->
  <c- k>column-width</c-><c- p>:</c-> <c- m>45</c-><c- l>px</c-><c- p>;</c->
  <c- k>column-gap</c-><c- p>:</c-> <c- m>0</c-><c- p>;</c->
  <c- k>column-rule</c-><c- p>:</c-> none<c- p>;</c->
<c- p>}</c->
</pre>
    <p>The available space is smaller than the specified column width
		and the actual column width will therefore be decreased.</p>
   </div>
   <p>To ensure that <a class="property" data-link-type="propdesc" href="#propdef-column-width" id="ref-for-propdef-column-width④">column-width</a> can be used with vertical text,
	column width means the length of the line boxes inside the columns.</p>
   <p class="note" role="note"><span>Note:</span> The reason for making <a class="property" data-link-type="propdesc" href="#propdef-column-width" id="ref-for-propdef-column-width⑤">column-width</a> somewhat flexible
	is to achieve scalable designs that can fit many screen sizes. 
	To set an exact column width, 
	the column gap and the width of the multicol container (assuming horizontal text) 
	must also be specified.</p>
   <h3 class="heading settled" data-level="3.2" id="cc"><span class="secno">3.2. </span><span class="content">The Number of Columns: the <a class="property" data-link-type="propdesc" href="#propdef-column-count" id="ref-for-propdef-column-count④">column-count</a> property</span><a class="self-link" href="#cc"></a></h3>
   <table class="def propdef" data-link-for-hint="column-count">
    <tbody>
     <tr>
      <th>Name:
      <td><dfn class="dfn-paneled css" data-dfn-type="property" data-export id="propdef-column-count">column-count</dfn>
     <tr class="value">
      <th><a href="https://drafts.csswg.org/css-values/#value-defs">Value:</a>
      <td class="prod">auto <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-4/#comb-one" id="ref-for-comb-one①">|</a> <a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-3/#integer-value" id="ref-for-integer-value">&lt;integer></a> 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#initial-values">Initial:</a>
      <td>auto 
     <tr>
      <th>Applies to:
      <td><a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#block-container" id="ref-for-block-container②">block containers</a> except <a data-link-type="dfn" href="https://drafts.csswg.org/css-tables-3/#table-wrapper-box" id="ref-for-table-wrapper-box①">table wrapper boxes</a> 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#inherited-property">Inherited:</a>
      <td>no 
     <tr>
      <th><a href="https://drafts.csswg.org/css-values/#percentages">Percentages:</a>
      <td>N/A 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#computed">Computed value:</a>
      <td>specified value 
     <tr>
      <th>Canonical order:
      <td>per grammar 
     <tr>
      <th><a href="https://drafts.csswg.org/web-animations/#animation-type">Animatable:</a>
      <td>by computed value 
   </table>
   <p>This property describes the number of columns of a <a data-link-type="dfn" href="#multi-column-container" id="ref-for-multi-column-container⑧">multicol container</a>.</p>
   <dl>
    <dt><dfn class="css" data-dfn-for="column-count" data-dfn-type="value" data-export id="valdef-column-count-auto">auto<a class="self-link" href="#valdef-column-count-auto"></a></dfn> 
    <dd> means that the number of columns will be determined by other properties
			(e.g., <a class="property" data-link-type="propdesc" href="#propdef-column-width" id="ref-for-propdef-column-width⑥">column-width</a>, 
			if it has a non-auto value). 
    <dt><dfn class="css" data-dfn-for="column-count" data-dfn-type="value" data-export id="valdef-column-count-integer"><a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-3/#integer-value" id="ref-for-integer-value①">&lt;integer></a><a class="self-link" href="#valdef-column-count-integer"></a></dfn>
    <dd> describes the optimal number of columns into which the content of the element will be flowed. 
			Values must be greater than 0. 
			If both <a class="property" data-link-type="propdesc" href="#propdef-column-width" id="ref-for-propdef-column-width⑦">column-width</a> and <a class="property" data-link-type="propdesc" href="#propdef-column-count" id="ref-for-propdef-column-count⑤">column-count</a> have non-auto values, 
			the integer value describes the maximum number of columns. 
   </dl>
   <div class="example" id="example-6acd2708">
    <a class="self-link" href="#example-6acd2708"></a> Example: 
<pre class="highlight"><c- f>body </c-><c- p>{</c-> <c- k>column-count</c-><c- p>:</c-> <c- m>3</c-> <c- p>}</c-></pre>
   </div>
   <h3 class="heading settled" data-level="3.3" id="columns"><span class="secno">3.3. </span><span class="content">The <a class="property" data-link-type="propdesc" href="#propdef-column-width" id="ref-for-propdef-column-width⑧">column-width</a> and <a class="property" data-link-type="propdesc" href="#propdef-column-count" id="ref-for-propdef-column-count⑥">column-count</a> Shorthand: The <a class="property" data-link-type="propdesc" href="#propdef-columns" id="ref-for-propdef-columns②">columns</a> Property</span><a class="self-link" href="#columns"></a></h3>
   <table class="def propdef" data-link-for-hint="columns">
    <tbody>
     <tr>
      <th>Name:
      <td><dfn class="dfn-paneled css" data-dfn-type="property" data-export id="propdef-columns">columns</dfn>
     <tr class="value">
      <th><a href="https://drafts.csswg.org/css-values/#value-defs">Value:</a>
      <td class="prod"><a class="production" data-link-type="propdesc" href="#propdef-column-width" id="ref-for-propdef-column-width⑨">&lt;'column-width'></a> <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-4/#comb-any" id="ref-for-comb-any">||</a> <a class="production" data-link-type="propdesc" href="#propdef-column-count" id="ref-for-propdef-column-count⑦">&lt;'column-count'></a> 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#initial-values">Initial:</a>
      <td>see individual properties 
     <tr>
      <th>Applies to:
      <td>see individual properties 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#inherited-property">Inherited:</a>
      <td>see individual properties 
     <tr>
      <th><a href="https://drafts.csswg.org/css-values/#percentages">Percentages:</a>
      <td>see individual properties 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#computed">Computed value:</a>
      <td>see individual properties 
     <tr>
      <th><a href="https://drafts.csswg.org/web-animations/#animation-type">Animation type:</a>
      <td>see individual properties 
     <tr>
      <th>Canonical order:
      <td>per grammar 
   </table>
   <p>This is a shorthand property for setting <a class="property" data-link-type="propdesc" href="#propdef-column-width" id="ref-for-propdef-column-width①⓪">column-width</a> and <a class="property" data-link-type="propdesc" href="#propdef-column-count" id="ref-for-propdef-column-count⑧">column-count</a>.
	Omitted values are set to their initial values.</p>
   <div class="example" id="example-628937c1">
    <a class="self-link" href="#example-628937c1"></a> Here are some valid declarations using the <a class="property" data-link-type="propdesc" href="#propdef-columns" id="ref-for-propdef-columns③">columns</a> property: 
<pre class="highlight">columns: 12em;      <c- c>/* column-width: 12em; column-count: auto */</c->
columns: auto 12em; <c- c>/* column-width: 12em; column-count: auto */</c->
columns: 2;         <c- c>/* column-width: auto; column-count: 2 */</c->
columns: 2 auto;    <c- c>/* column-width: auto; column-count: 2 */</c->
columns: auto;      <c- c>/* column-width: auto; column-count: auto */</c->
columns: auto auto; <c- c>/* column-width: auto; column-count: auto */</c->
</pre>
   </div>
   <h3 class="heading settled" data-level="3.4" id="pseudo-algorithm"><span class="secno">3.4. </span><span class="content">The Pseudo-algorithm</span><a class="self-link" href="#pseudo-algorithm"></a></h3>
   <p>The pseudo-algorithm below determines the used values for <a class="property" data-link-type="propdesc" href="#propdef-column-count" id="ref-for-propdef-column-count⑨">column-count</a> (N) and <a class="property" data-link-type="propdesc" href="#propdef-column-width" id="ref-for-propdef-column-width①①">column-width</a> (W). There is one other variable
	in the pseudo-algorithm: U is the used width of the multi-column container.</p>
   <p class="note" role="note"><span>Note:</span> The used width U of the multi-column container can depend on the element’s contents,
	in which case it also depends on the computed values of the <a class="property" data-link-type="propdesc" href="#propdef-column-count" id="ref-for-propdef-column-count①⓪">column-count</a> and <a class="property" data-link-type="propdesc" href="#propdef-column-width" id="ref-for-propdef-column-width①②">column-width</a> properties.
	This specification does not define how U is calculated.
	Another module (probably the Basic Box Model <a data-link-type="biblio" href="#biblio-css3box">[CSS3BOX]</a> or the Intrinsic &amp; Extrinsic Sizing Module <a data-link-type="biblio" href="#biblio-css3-sizing">[CSS3-SIZING]</a>) is expected to define this.</p>
   <p>The <code>floor(X)</code> function returns the largest integer Y ≤ X.</p>
<pre>(01)  if ((column-width = auto) and (column-count = auto)) then
(02)      exit; /* not a multicol container */
(03)  if column-width = auto then
(04)      N := column-count
(05)  else if column-count = auto then
(06)      N := max(1,
(07)        floor((U + column-gap)/(column-width + column-gap)))
(08)  else
(09)      N := min(column-count, max(1,
(10)        floor((U + column-gap)/(column-width + column-gap))))
</pre>
   <p>And:</p>
<pre>(11)  W := max(0, ((U + column-gap)/N - column-gap))
</pre>
   <p>For the purpose of finding the number of auto-repeated columns,
	the UA must floor the column size to a UA-specified value to avoid division by zero. 
	It is suggested that this floor be 1px or less.</p>
   <p>In fragmented contexts such as in paged media,
	user agents may perform this calculation on a per-fragment basis.</p>
   <p>The used value for <a class="property" data-link-type="propdesc" href="#propdef-column-count" id="ref-for-propdef-column-count①①">column-count</a> is calculated without regard for explicit column breaks or constrained column heights,
	while the actual value takes these into consideration.</p>
   <div class="example" id="example-855fb04e">
    <a class="self-link" href="#example-855fb04e"></a> In this example, the actual column-count is higher than the used column-count 
		due to explicit column breaks: 
<pre class="highlight"><c- f>div </c-><c- p>{</c->
  <c- k>width</c-><c- p>:</c-> <c- m>40</c-><c- l>em</c-><c- p>;</c->
  <c- k>columns</c-><c- p>:</c-> <c- m>20</c-><c- l>em</c-><c- p>;</c->
  <c- k>column-gap</c-><c- p>:</c-> <c- m>0</c-><c- p>;</c->
<c- p>}</c->

<c- f>p </c-><c- p>{</c->
  <c- k>break-after</c-><c- p>:</c-> column<c- p>;</c->
<c- p>}</c->
</pre>
<pre class="highlight"><c- p>&lt;</c-><c- f>div</c-><c- p>></c->
  <c- p>&lt;</c-><c- f>p</c-><c- p>></c->one
  <c- p>&lt;</c-><c- f>p</c-><c- p>></c->two
  <c- p>&lt;</c-><c- f>p</c-><c- p>></c->three
<c- p>&lt;/</c-><c- f>div</c-><c- p>></c->
</pre>
    <figure>
      <img alt="Two columns drawn inside the container, one outside" src="images/column-count-higher-than-used-count.svg"> 
     <figcaption>The computed column-count is auto, the used column-count is 2 and the actual column-count is 3.</figcaption>
    </figure>
   </div>
   <div class="example" id="example-69e715d6">
    <a class="self-link" href="#example-69e715d6"></a> The actual column-count may be lower than the used column-count. 
		Consider this example: 
<pre class="highlight"><c- f>div </c-><c- p>{</c->
  <c- k>width</c-><c- p>:</c-> <c- m>80</c-><c- l>em</c-><c- p>;</c->
  <c- k>height</c-><c- p>:</c-> <c- m>10</c-><c- l>em</c-><c- p>;</c->
  <c- k>columns</c-><c- p>:</c-> <c- m>20</c-><c- l>em</c-><c- p>;</c->
  <c- k>column-gap</c-><c- p>:</c-> <c- m>0</c-><c- p>;</c->
  <c- k>column-fill</c-><c- p>:</c-> auto<c- p>;</c->
<c- p>}</c->
</pre>
<pre class="highlight"><c- p>&lt;</c-><c- f>div</c-><c- p>></c->foo<c- p>&lt;/</c-><c- f>div</c-><c- p>></c->
</pre>
    <p>The computed column-count is auto,
		the used column-count is 4, 
		and the actual column-count is 1.</p>
   </div>
   <h3 class="heading settled" data-level="3.5" id="stacking-context"><span class="secno">3.5. </span><span class="content"> Stacking Context</span><a class="self-link" href="#stacking-context"></a></h3>
   <p>All column boxes in a multi-column container are in the same stacking context
	and the drawing order of their contents is as specified in CSS 2.1. 
	Column boxes do not establish new stacking contexts.</p>
   <h2 class="heading settled" data-level="4" id="column-gaps-and-rules"><span class="secno">4. </span><span class="content">Column Gaps and Rules</span><a class="self-link" href="#column-gaps-and-rules"></a></h2>
   <p>Column gaps and rules are placed between columns in the same <a data-link-type="dfn" href="#multi-column-container" id="ref-for-multi-column-container⑨">multicol container</a>.
	The length of the column gaps and column rules is equal to the column height. 
	Column gaps take up space. 
	That is, column gaps will push apart content in adjacent columns 
	(within the same <span id="ref-for-multi-column-container①⓪">multicol container</span>).</p>
   <p>A <a data-link-type="dfn" href="#column-rule" id="ref-for-column-rule①">column rule</a> is drawn in the middle of the <a data-link-type="dfn" href="#column-gap" id="ref-for-column-gap①">column gap</a> with the endpoints at opposing content edges of the <a data-link-type="dfn" href="#multi-column-container" id="ref-for-multi-column-container①①">multicol container</a>. 
	Column rules do not take up space. 
	That is, the presence or thickness of a <span id="ref-for-column-rule②">column rule</span> will not alter the placement of anything else. 
	If a <span id="ref-for-column-rule③">column rule</span> is wider than its gap, 
	the adjacent column boxes will overlap the rule, 
	and the rule may possibly extend outside the box of the <span id="ref-for-multi-column-container①②">multicol container</span>. 
	Column rules are painted just above the border of the <span id="ref-for-multi-column-container①③">multicol container</span>. 
	For scrollable multicol containers, 
	note that while the border and background of the <span id="ref-for-multi-column-container①④">multicol container</span> obviously aren’t scrolled, 
	the rules need to scroll along with the columns. 
	Column rules are only drawn between two columns that both have content.</p>
   <h3 class="heading settled" data-level="4.1" id="cg"><span class="secno">4.1. </span><span class="content">Gutters Between Columns: the <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-align-3/#propdef-column-gap" id="ref-for-propdef-column-gap">column-gap</a> property</span><a class="self-link" href="#cg"></a></h3>
   <p>The <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-align-3/#propdef-column-gap" id="ref-for-propdef-column-gap①">column-gap</a> property is defined in <a data-link-type="biblio" href="#biblio-css3-align">[CSS3-ALIGN]</a>.</p>
   <p>In a <a data-link-type="dfn" href="#multi-column-formatting-context" id="ref-for-multi-column-formatting-context">multi-column formatting context</a> the used value of <a class="css" data-link-type="maybe" href="https://drafts.csswg.org/css-align-3/#valdef-row-gap-normal" id="ref-for-valdef-row-gap-normal">normal</a> for the <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-align-3/#propdef-column-gap" id="ref-for-propdef-column-gap②">column-gap</a> property is <span class="css">1em</span>. 
	This ensures columns are readable when the initial values are used.
	If there is a column rule between columns, 
	it will appear in the middle of the gap.</p>
   <h3 class="heading settled" data-level="4.2" id="crc"><span class="secno">4.2. </span><span class="content">The Color of Column Rules: the <a class="property" data-link-type="propdesc" href="#propdef-column-rule-color" id="ref-for-propdef-column-rule-color">column-rule-color</a> property</span><a class="self-link" href="#crc"></a></h3>
   <table class="def propdef" data-link-for-hint="column-rule-color">
    <tbody>
     <tr>
      <th>Name:
      <td><dfn class="dfn-paneled css" data-dfn-type="property" data-export id="propdef-column-rule-color">column-rule-color</dfn>
     <tr class="value">
      <th><a href="https://drafts.csswg.org/css-values/#value-defs">Value:</a>
      <td class="prod"><a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-color-3/#valuea-def-color" id="ref-for-valuea-def-color" title="Expands to: indigo | gold | firebrick | indianred | yellow | darkolivegreen | darkseagreen | slategrey | darkslategrey | mediumvioletred | mediumorchid | transparent | chartreuse | mediumslateblue | black | springgreen | crimson | lightsalmon | brown | turquoise | olivedrab | cyan | silver | skyblue | gray | darkturquoise | goldenrod | darkgreen | darkviolet | darkgray | lightpink | teal | darkmagenta | lightgoldenrodyellow | lavender | yellowgreen | thistle | violet | navy | dimgrey | orchid | blue | ghostwhite | honeydew | cornflowerblue | darkblue | darkkhaki | mediumpurple | cornsilk | red | bisque | slategray | darkcyan | khaki | wheat | deepskyblue | rebeccapurple | darkred | steelblue | aliceblue | lightslategrey | gainsboro | mediumturquoise | floralwhite | coral | purple | lightgrey | lightcyan | darksalmon | beige | azure | lightsteelblue | oldlace | greenyellow | royalblue | lightseagreen | mistyrose | sienna | lightcoral | orangered | navajowhite | lime | palegreen | burlywood | seashell | mediumspringgreen | fuchsia | papayawhip | blanchedalmond | peru | aquamarine | white | darkslategray | tomato | ivory | dodgerblue | currentcolor | lemonchiffon | chocolate | orange | forestgreen | darkgrey | olive | mintcream | antiquewhite | darkorange | cadetblue | moccasin | limegreen | saddlebrown | grey | darkslateblue | lightskyblue | deeppink | plum | aqua | darkgoldenrod | maroon | sandybrown | magenta | tan | rosybrown | pink | lightblue | palevioletred | mediumseagreen | slateblue | dimgray | powderblue | seagreen | snow | mediumblue | midnightblue | paleturquoise | palegoldenrod | whitesmoke | darkorchid | salmon | lightslategray | lawngreen | lightgreen | lightgray | hotpink | lightyellow | lavenderblush | linen | mediumaquamarine | green | blueviolet | peachpuff">&lt;color></a> 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#initial-values">Initial:</a>
      <td>currentcolor 
     <tr>
      <th>Applies to:
      <td>multicol containers 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#inherited-property">Inherited:</a>
      <td>no 
     <tr>
      <th><a href="https://drafts.csswg.org/css-values/#percentages">Percentages:</a>
      <td>N/A 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#computed">Computed value:</a>
      <td>computed color 
     <tr>
      <th>Canonical order:
      <td>per grammar 
     <tr>
      <th><a href="https://drafts.csswg.org/web-animations/#animation-type">Animation type:</a>
      <td>by computed value type 
   </table>
   <dl>
    <dt><dfn class="css" data-dfn-for="column-rule-color" data-dfn-type="value" data-export id="valdef-column-rule-color-color"><a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-color-3/#valuea-def-color" id="ref-for-valuea-def-color①" title="Expands to: indigo | gold | firebrick | indianred | yellow | darkolivegreen | darkseagreen | slategrey | darkslategrey | mediumvioletred | mediumorchid | transparent | chartreuse | mediumslateblue | black | springgreen | crimson | lightsalmon | brown | turquoise | olivedrab | cyan | silver | skyblue | gray | darkturquoise | goldenrod | darkgreen | darkviolet | darkgray | lightpink | teal | darkmagenta | lightgoldenrodyellow | lavender | yellowgreen | thistle | violet | navy | dimgrey | orchid | blue | ghostwhite | honeydew | cornflowerblue | darkblue | darkkhaki | mediumpurple | cornsilk | red | bisque | slategray | darkcyan | khaki | wheat | deepskyblue | rebeccapurple | darkred | steelblue | aliceblue | lightslategrey | gainsboro | mediumturquoise | floralwhite | coral | purple | lightgrey | lightcyan | darksalmon | beige | azure | lightsteelblue | oldlace | greenyellow | royalblue | lightseagreen | mistyrose | sienna | lightcoral | orangered | navajowhite | lime | palegreen | burlywood | seashell | mediumspringgreen | fuchsia | papayawhip | blanchedalmond | peru | aquamarine | white | darkslategray | tomato | ivory | dodgerblue | currentcolor | lemonchiffon | chocolate | orange | forestgreen | darkgrey | olive | mintcream | antiquewhite | darkorange | cadetblue | moccasin | limegreen | saddlebrown | grey | darkslateblue | lightskyblue | deeppink | plum | aqua | darkgoldenrod | maroon | sandybrown | magenta | tan | rosybrown | pink | lightblue | palevioletred | mediumseagreen | slateblue | dimgray | powderblue | seagreen | snow | mediumblue | midnightblue | paleturquoise | palegoldenrod | whitesmoke | darkorchid | salmon | lightslategray | lawngreen | lightgreen | lightgray | hotpink | lightyellow | lavenderblush | linen | mediumaquamarine | green | blueviolet | peachpuff">&lt;color></a><a class="self-link" href="#valdef-column-rule-color-color"></a></dfn>
    <dd> Specifies the color of the <a data-link-type="dfn" href="#column-rule" id="ref-for-column-rule④">column rule</a>. 
   </dl>
   <h3 class="heading settled" data-level="4.3" id="crs"><span class="secno">4.3. </span><span class="content">The Style Of Column Rules: the <a class="property" data-link-type="propdesc" href="#propdef-column-rule-style" id="ref-for-propdef-column-rule-style">column-rule-style</a> property</span><a class="self-link" href="#crs"></a></h3>
   <table class="def propdef" data-link-for-hint="column-rule-style">
    <tbody>
     <tr>
      <th>Name:
      <td><dfn class="dfn-paneled css" data-dfn-type="property" data-export id="propdef-column-rule-style">column-rule-style</dfn>
     <tr class="value">
      <th><a href="https://drafts.csswg.org/css-values/#value-defs">Value:</a>
      <td class="prod"><a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-backgrounds-3/#typedef-line-style" id="ref-for-typedef-line-style" title="Expands to: none | ridge | dotted | solid | dashed | outset | inset | double | hidden | groove">&lt;line-style></a> 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#initial-values">Initial:</a>
      <td>none 
     <tr>
      <th>Applies to:
      <td>multicol containers 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#inherited-property">Inherited:</a>
      <td>no 
     <tr>
      <th><a href="https://drafts.csswg.org/css-values/#percentages">Percentages:</a>
      <td>N/A 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#computed">Computed value:</a>
      <td>specified keyword 
     <tr>
      <th>Canonical order:
      <td>per grammar 
     <tr>
      <th><a href="https://drafts.csswg.org/web-animations/#animation-type">Animation type:</a>
      <td>discrete 
   </table>
   <p>The <a class="property" data-link-type="propdesc" href="#propdef-column-rule-style" id="ref-for-propdef-column-rule-style①">column-rule-style</a> property sets the style of the rule between columns of an element.
	The <a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-backgrounds-3/#typedef-line-style" id="ref-for-typedef-line-style①" title="Expands to: none | ridge | dotted | solid | dashed | outset | inset | double | hidden | groove">&lt;line-style></a> values are interpreted as in the <a href="https://www.w3.org/TR/CSS2/tables.html#collapsing-borders">collapsing border model</a>.</p>
   <p>The <a class="css" data-link-type="maybe" href="https://drafts.csswg.org/css-backgrounds-3/#valdef-line-style-none" id="ref-for-valdef-line-style-none">none</a> value forces the computed value of <a class="property" data-link-type="propdesc" href="#propdef-column-rule-width" id="ref-for-propdef-column-rule-width">column-rule-width</a> to be <span class="css">0</span>.</p>
   <h3 class="heading settled" data-level="4.4" id="crw"><span class="secno">4.4. </span><span class="content">The Width Of Column Rules: the <a class="property" data-link-type="propdesc" href="#propdef-column-rule-width" id="ref-for-propdef-column-rule-width①">column-rule-width</a> property</span><a class="self-link" href="#crw"></a></h3>
   <table class="def propdef" data-link-for-hint="column-rule-width">
    <tbody>
     <tr>
      <th>Name:
      <td><dfn class="dfn-paneled css" data-dfn-type="property" data-export id="propdef-column-rule-width">column-rule-width</dfn>
     <tr class="value">
      <th><a href="https://drafts.csswg.org/css-values/#value-defs">Value:</a>
      <td class="prod"><a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-backgrounds-3/#typedef-line-width" id="ref-for-typedef-line-width" title="Expands to: thick | medium | thin">&lt;line-width></a> 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#initial-values">Initial:</a>
      <td>medium 
     <tr>
      <th>Applies to:
      <td>multicol containers 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#inherited-property">Inherited:</a>
      <td>no 
     <tr>
      <th><a href="https://drafts.csswg.org/css-values/#percentages">Percentages:</a>
      <td>N/A 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#computed">Computed value:</a>
      <td>absolute length; <span class="css">0</span> if the column rule style is <a class="css" data-link-type="maybe" href="https://drafts.csswg.org/css-backgrounds-3/#valdef-line-style-none" id="ref-for-valdef-line-style-none①">none</a> or <a class="css" data-link-type="maybe" href="https://drafts.csswg.org/css-backgrounds-3/#valdef-line-style-hidden" id="ref-for-valdef-line-style-hidden">hidden</a> 
     <tr>
      <th>Canonical order:
      <td>per grammar 
     <tr>
      <th><a href="https://drafts.csswg.org/web-animations/#animation-type">Animation type:</a>
      <td>by computed value type 
   </table>
   <p>This property sets the width of the rule between columns.
	Negative values are not allowed.</p>
   <h3 class="heading settled" data-level="4.5" id="cr"><span class="secno">4.5. </span><span class="content">Column Rule Shorthand: the <a class="property" data-link-type="propdesc" href="#propdef-column-rule" id="ref-for-propdef-column-rule④">column-rule</a> property</span><a class="self-link" href="#cr"></a></h3>
   <table class="def propdef" data-link-for-hint="column-rule">
    <tbody>
     <tr>
      <th>Name:
      <td><dfn class="dfn-paneled css" data-dfn-type="property" data-export id="propdef-column-rule">column-rule</dfn>
     <tr class="value">
      <th><a href="https://drafts.csswg.org/css-values/#value-defs">Value:</a>
      <td class="prod"><a class="production" data-link-type="propdesc" href="#propdef-column-rule-width" id="ref-for-propdef-column-rule-width②">&lt;'column-rule-width'></a> <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-4/#comb-any" id="ref-for-comb-any①">||</a> <a class="production" data-link-type="propdesc" href="#propdef-column-rule-style" id="ref-for-propdef-column-rule-style②">&lt;'column-rule-style'></a> <span id="ref-for-comb-any②">||</span> <a class="production" data-link-type="propdesc" href="#propdef-column-rule-color" id="ref-for-propdef-column-rule-color①">&lt;'column-rule-color'></a> 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#initial-values">Initial:</a>
      <td>see individual properties 
     <tr>
      <th>Applies to:
      <td>see individual properties 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#inherited-property">Inherited:</a>
      <td>see individual properties 
     <tr>
      <th><a href="https://drafts.csswg.org/css-values/#percentages">Percentages:</a>
      <td>see individual properties 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#computed">Computed value:</a>
      <td>see individual properties 
     <tr>
      <th><a href="https://drafts.csswg.org/web-animations/#animation-type">Animation type:</a>
      <td>see individual properties 
     <tr>
      <th>Canonical order:
      <td>per grammar 
   </table>
   <p>This property is a shorthand for setting <a class="property" data-link-type="propdesc" href="#propdef-column-rule-width" id="ref-for-propdef-column-rule-width③">column-rule-width</a>, <a class="property" data-link-type="propdesc" href="#propdef-column-rule-style" id="ref-for-propdef-column-rule-style③">column-rule-style</a>, and <a class="property" data-link-type="propdesc" href="#propdef-column-rule-color" id="ref-for-propdef-column-rule-color②">column-rule-color</a> at the same place in the style sheet. 
	Omitted values are set to their initial values.</p>
   <div class="example" id="example-31902657">
    <a class="self-link" href="#example-31902657"></a> In this example, the <a data-link-type="dfn" href="#column-rule" id="ref-for-column-rule⑤">column rule</a> and the <a data-link-type="dfn" href="#column-gap" id="ref-for-column-gap②">column gap</a> have the same width. 
		Therefore, they will occupy exactly the same space. 
<pre class="highlight"><c- f>body </c-><c- p>{</c->
  <c- k>column-gap</c-><c- p>:</c-> <c- m>35</c-><c- l>px</c-><c- p>;</c->
  <c- k>column-rule-width</c-><c- p>:</c-> <c- m>35</c-><c- l>px</c-><c- p>;</c->
  <c- k>column-rule-style</c-><c- p>:</c-> solid<c- p>;</c->
  <c- k>column-rule-color</c-><c- p>:</c-> black<c- p>;</c->
<c- p>}</c->
</pre>
    <figure>
      <img alt="The rule completely covers any gap." src="images/rule-same-width-as-gap.svg"> 
     <figcaption>The column rule and column gap occupy the same space.</figcaption>
    </figure>
   </div>
   <h2 class="heading settled" data-level="5" id="column-breaks"><span class="secno">5. </span><span class="content"> Column Breaks</span><a class="self-link" href="#column-breaks"></a></h2>
   <p>When content is laid out in multiple columns,
	the user agent must determine where column breaks are placed. 
	The problem of breaking content into columns is similar to breaking content into pages, 
	which is described in CSS 2.1, section 13.3.3 <a data-link-type="biblio" href="#biblio-css21">[CSS21]</a>.</p>
   <p>Three new properties are introduced to allow column breaks to be described in the same properties as page breaks: <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-break-3/#propdef-break-before" id="ref-for-propdef-break-before">break-before</a>, <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-break-3/#propdef-break-after" id="ref-for-propdef-break-after">break-after</a>, and <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-break-3/#propdef-break-inside" id="ref-for-propdef-break-inside">break-inside</a>.</p>
   <h3 class="heading settled" data-level="5.1" id="break-before-break-after-break-inside"><span class="secno">5.1. </span><span class="content">Controlling Fragmentation: the <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-break-3/#propdef-break-before" id="ref-for-propdef-break-before①">break-before</a>, <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-break-3/#propdef-break-after" id="ref-for-propdef-break-after①">break-after</a>, <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-break-3/#propdef-break-inside" id="ref-for-propdef-break-inside①">break-inside</a> properties</span><a class="self-link" href="#break-before-break-after-break-inside"></a></h3>
   <p><a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-break-3/#propdef-break-before" id="ref-for-propdef-break-before②">break-before</a>, <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-break-3/#propdef-break-after" id="ref-for-propdef-break-after②">break-after</a>, and <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-break-3/#propdef-break-inside" id="ref-for-propdef-break-inside②">break-inside</a> are defined in <a data-link-type="biblio" href="#biblio-css3-break">[CSS3-BREAK]</a>.</p>
   <h2 class="heading settled" data-level="6" id="spanning-columns"><span class="secno">6. </span><span class="content"> Spanning Columns</span><a class="self-link" href="#spanning-columns"></a></h2>
   <p>The <a class="property" data-link-type="propdesc" href="#propdef-column-span" id="ref-for-propdef-column-span①">column-span</a> property makes it possible for an element to span across several columns.</p>
   <h3 class="heading settled" data-level="6.1" id="column-span"><span class="secno">6.1. </span><span class="content">Spanning An Element Across Columns: the <a class="property" data-link-type="propdesc" href="#propdef-column-span" id="ref-for-propdef-column-span②">column-span</a> property</span><a class="self-link" href="#column-span"></a></h3>
   <table class="def propdef" data-link-for-hint="column-span">
    <tbody>
     <tr>
      <th>Name:
      <td><dfn class="dfn-paneled css" data-dfn-type="property" data-export id="propdef-column-span">column-span</dfn>
     <tr class="value">
      <th><a href="https://drafts.csswg.org/css-values/#value-defs">Value:</a>
      <td class="prod">none <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-4/#comb-one" id="ref-for-comb-one②">|</a> all 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#initial-values">Initial:</a>
      <td>none 
     <tr>
      <th>Applies to:
      <td>in-flow block-level elements 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#inherited-property">Inherited:</a>
      <td>no 
     <tr>
      <th><a href="https://drafts.csswg.org/css-values/#percentages">Percentages:</a>
      <td>N/A 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#computed">Computed value:</a>
      <td>specified keyword 
     <tr>
      <th>Canonical order:
      <td>per grammar 
     <tr>
      <th><a href="https://drafts.csswg.org/web-animations/#animation-type">Animation type:</a>
      <td>discrete 
   </table>
   <p>This property describes how many columns an element spans across. Values are:</p>
   <dl>
    <dt><dfn class="dfn-paneled css" data-dfn-for="column-span" data-dfn-type="value" data-export id="valdef-column-span-none">none</dfn>
    <dd> The element does not span multiple columns. 
    <dt><dfn class="dfn-paneled css" data-dfn-for="column-span" data-dfn-type="value" data-export id="valdef-column-span-all">all</dfn>
    <dd>
      The element is taken <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#out-of-flow" id="ref-for-out-of-flow">out-of-flow</a> and spans across all columns of the nearest multicol ancestor 
			in the same <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#block-formatting-context" id="ref-for-block-formatting-context③">block formatting context</a>.
			Content in the normal flow that appears before the element 
			is automatically balanced across all columns 
			in the immediately preceding <a data-link-type="dfn" href="#multi-column-line" id="ref-for-multi-column-line④">multi-column line</a> before the element appears.
			The element establishes an <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#independent-formatting-context" id="ref-for-independent-formatting-context②">independent formatting context</a>. 
     <p class="note" role="note"><span>Note:</span> Whether the element establishes a new <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#formatting-context" id="ref-for-formatting-context">formatting context</a> does not depend on whether the element is a descendent of a multicol or not.
			When <a class="property" data-link-type="propdesc" href="#propdef-column-span" id="ref-for-propdef-column-span③">column-span</a> is <a class="css" data-link-type="maybe" href="#valdef-column-span-all" id="ref-for-valdef-column-span-all">all</a>, it always does.
			This helps with robustness of designs to later revisions that remove the multicol,
			or when media queries turn the multicol off in some situations.</p>
   </dl>
   <p>An element that spans more than one column is called a <dfn data-dfn-type="dfn" data-export id="spanning-element">spanning element<a class="self-link" href="#spanning-element"></a></dfn> and the box it creates is called a <dfn class="dfn-paneled" data-dfn-type="dfn" data-export id="spanner">spanner</dfn>.</p>
   <p>A spanning element is taken <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#out-of-flow" id="ref-for-out-of-flow①">out-of-flow</a>, leaving a forced break.
	This does not affect the <a href="https://www.w3.org/TR/CSS2/zindex.html">painting order</a> <a data-link-type="biblio" href="#biblio-css21">[CSS21]</a> of the spanning element.</p>
   <div class="example" id="example-2c18fd19">
    <a class="self-link" href="#example-2c18fd19"></a> In this example, an <code>h2</code> element has been added to the sample document after the sixth sentence 
		(i.e., after the words "the leg of a"). 
		This styling applies: 
<pre class="highlight"><c- f>h2 </c-><c- p>{</c-> <c- k>column-span</c-><c- p>:</c-> all<c- p>;</c-> <c- k>background</c-><c- p>:</c-> silver <c- p>}</c->
</pre>
    <p>By setting <a class="property" data-link-type="propdesc" href="#propdef-column-span" id="ref-for-propdef-column-span④">column-span</a> to <a class="css" data-link-type="maybe" href="#valdef-column-span-all" id="ref-for-valdef-column-span-all①">all</a>,
		all content that appears before the <code>h2</code> element 
		is shown before the <code>h2</code> element.</p>
    <figure>
      <img alt="An element spans all three columns" src="images/h2-spanner.svg"> 
     <figcaption>The h2 element is set to column-span: all</figcaption>
    </figure>
   </div>
   <p>A spanning element may be lower than the first level of descendants
	as long as they are part of the same <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#formatting-context" id="ref-for-formatting-context①">formatting context</a>. 
	If the fragment before the spanner is empty, nothing special happens; 
	the top margin/border/padding is above the spanning element, as an empty <a data-link-type="dfn" href="https://drafts.csswg.org/css-break-4/#fragment" id="ref-for-fragment①">fragment</a>.</p>
   <div class="example" id="example-fa0001d6">
    <a class="self-link" href="#example-fa0001d6"></a> In this example the <a data-link-type="dfn" href="#multi-column-container" id="ref-for-multi-column-container①⑤">multicol container</a> is the <code>article</code> element. 
		Inside this parent is a paragraph and then a section element. 
		The section contains an <code>h2</code> heading set to <a class="css" data-link-type="maybe" href="#valdef-column-span-all" id="ref-for-valdef-column-span-all②">all</a> this spans all three columns while the containing section remains inside the column boxes. 
    <p>The <code>h2</code> is the first child of the section.
		This means that the margin, 
		border (shown in red in the diagram) 
		and padding on this section appear before the spanning <code>h2</code> as an empty fragment.</p>
<pre class="highlight"><c- p>&lt;</c-><c- f>article</c-><c- p>></c->
  <c- p>&lt;</c-><c- f>p</c-><c- p>></c->...<c- p>&lt;/</c-><c- f>p</c-><c- p>></c->
  <c- p>&lt;</c-><c- f>section</c-><c- p>></c->
    <c- p>&lt;</c-><c- f>h2</c-><c- p>></c->An h2 element<c- p>&lt;/</c-><c- f>h2</c-><c- p>></c->
    <c- p>&lt;</c-><c- f>p</c-><c- p>></c->...<c- p>&lt;/</c-><c- f>p</c-><c- p>></c->
  <c- p>&lt;/</c-><c- f>section</c-><c- p>></c->
<c- p>&lt;/</c-><c- f>article</c-><c- p>></c->
</pre>
<pre class="highlight"><c- f>section </c-><c- p>{</c->
  <c- k>border</c-><c- p>:</c-> <c- m>2</c-><c- l>px</c-> solid red<c- p>;</c->
  <c- k>margin-top</c-><c- p>:</c-> <c- m>65</c-><c- l>px</c-><c- p>;</c->
  <c- k>padding-top</c-><c- p>:</c-> <c- m>20</c-><c- l>px</c-><c- p>;</c->
<c- p>}</c->

<c- f>h2 </c-><c- p>{</c->
  <c- k>column-span</c-><c- p>:</c-> all<c- p>;</c->
  <c- k>background</c-><c- p>:</c-> silver
<c- p>}</c->
</pre>
    <figure>
      <img alt="An element spans all three columns, the red border around the section breaks before the spanner." src="images/nested-spanner.svg"> 
     <figcaption>The <code>h2</code> element is set to <a class="css" data-link-type="propdesc" href="#propdef-column-span" id="ref-for-propdef-column-span⑤">column-span: all</a>, 
		the section has a red border and top padding and margin</figcaption>
    </figure>
   </div>
   <p>A spanning element takes up more space than the element would take up otherwise.
	When space is limited, it may be impossible to find room for the spanning element. 
	In these cases, user agents may treat the element as if <a class="css" data-link-type="maybe" href="#valdef-column-span-none" id="ref-for-valdef-column-span-none">none</a> had been specified on this property.</p>
   <div class="example" id="example-2980e0d6">
    <a class="self-link" href="#example-2980e0d6"></a> In this example, the <code>h2</code> element appears later in the content, 
		and the height of the multicol container is constrained. 
		Therefore, the <code>h2</code> element appears in the overflow 
		and there is not room to make the element spanning.
		As a result, the element appears as if <a class="css" data-link-type="propdesc" href="#propdef-column-span" id="ref-for-propdef-column-span⑥">column-span: none</a> was specified. 
    <figure>
      <img alt="The h2 element is in an overflow column" src="images/h2-in-the-overflow-no-span.svg" style="max-height: 107px;"> 
     <figcaption>The h2 element is in an overflow column and appears as if column-span none is specified</figcaption>
    </figure>
   </div>
   <div class="example" id="example-e49da6ca">
    <a class="self-link" href="#example-e49da6ca"></a> This example is similar to the previous example,
		except that the H2 element appears naturally in the last column.
		Still, there is not enough room to make the element spanning. 
    <figure>
      <img alt="The h2 element is in the final column" src="images/h2-in-the-last-column-no-span.svg" style="max-height: 107px;"> 
     <figcaption>The h2 element is in the final column and appears as if column-span none is specified</figcaption>
    </figure>
   </div>
   <div class="example" id="example-8f69cecc">
    <a class="self-link" href="#example-8f69cecc"></a> In fragmented contexts spanning elements are honored in all fragments.
		In this example, we are in paged media, 
		and the first three paragraphs have column breaks after them.
		A spanning <code>H2</code> element appears after the fourth paragraph. 
    <figure>
      <img alt="Three columns with two lines of text each" src="images/spanner-page-break1.svg"> 
     <figcaption>This would appear on the first page</figcaption>
    </figure>
    <figure>
      <img alt="A spanning element across the three columns, text above and below." src="images/spanner-page-break2.svg"> 
     <figcaption>This would appear on the second page</figcaption>
    </figure>
   </div>
   <p>Spanners are block-level boxes
	therefore the margins of two adjacent spanners will collapse with each other.
	As column boxes establish a new <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#block-formatting-context" id="ref-for-block-formatting-context④">block formatting context</a>,
	margins on elements inside a column box will not collapse with the margin of a spanner.</p>
   <div class="example" id="example-f82c16c7">
    <a class="self-link" href="#example-f82c16c7"></a> Spanners establish new <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#formatting-context" id="ref-for-formatting-context②">formatting contexts</a>, but their margins can be changed by their surroundings. 
		In this example, two spanners naturally end up at the top of a page. 
		The top margin of the first spanner is truncated due to adjoining an unforced break. 
		The margins between the two spanners collapse with each other. 
		However, the bottom margin of the second spanner does not collapse with the top margin of the subsequent element. 
<pre class="highlight"><c- f>h2 </c-><c- p>{</c->
  <c- k>margin</c-><c- p>:</c-> <c- m>16</c-><c- l>px</c-> <c- m>0</c-><c- p>;</c->
  <c- k>column-span</c-><c- p>:</c-> all<c- p>;</c->
  <c- k>background</c-><c- p>:</c-> silver
<c- p>}</c->
<c- f>p </c-><c- p>{</c-> <c- k>margin-top</c-><c- p>:</c-> <c- m>16</c-><c- l>px</c-> <c- p>}</c->
</pre>
    <figure>
      <img alt="Two spanning elements after a page break" src="images/two-spanners-margin-no-collapse.svg"> 
     <figcaption>Margins collapse between two spanning elements, but not the bottom margin of a spanner and top margin of next element.</figcaption>
    </figure>
   </div>
   <h2 class="heading settled" data-level="7" id="filling-columns"><span class="secno">7. </span><span class="content"> Filling Columns</span><a class="self-link" href="#filling-columns"></a></h2>
   <p>There are two strategies for filling columns:
	columns can either be balanced, or not. 
	If columns are balanced, user agents should try to minimize variations in column height, 
	while honoring forced breaks, <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-break-4/#propdef-widows" id="ref-for-propdef-widows">widows</a> and <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-break-3/#propdef-orphans" id="ref-for-propdef-orphans">orphans</a>, 
	and other properties that may affect column heights. 
	If columns are not balanced, they are filled sequentially; 
	some columns may end up partially filled, or with no content at all.</p>
   <h3 class="heading settled" data-level="7.1" id="cf"><span class="secno">7.1. </span><span class="content">Column Balancing: the <a class="property" data-link-type="propdesc" href="#propdef-column-fill" id="ref-for-propdef-column-fill①">column-fill</a> property</span><a class="self-link" href="#cf"></a></h3>
   <table class="def propdef" data-link-for-hint="column-fill">
    <tbody>
     <tr>
      <th>Name:
      <td><dfn class="dfn-paneled css" data-dfn-type="property" data-export id="propdef-column-fill">column-fill</dfn>
     <tr class="value">
      <th><a href="https://drafts.csswg.org/css-values/#value-defs">Value:</a>
      <td class="prod">auto <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-4/#comb-one" id="ref-for-comb-one③">|</a> balance <span id="ref-for-comb-one④">|</span> balance-all 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#initial-values">Initial:</a>
      <td>balance 
     <tr>
      <th>Applies to:
      <td>multicol containers 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#inherited-property">Inherited:</a>
      <td>no 
     <tr>
      <th><a href="https://drafts.csswg.org/css-values/#percentages">Percentages:</a>
      <td>N/A 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#computed">Computed value:</a>
      <td>specified keyword 
     <tr>
      <th>Canonical order:
      <td>per grammar 
     <tr>
      <th><a href="https://drafts.csswg.org/web-animations/#animation-type">Animation type:</a>
      <td>discrete 
   </table>
   <p>The values are:</p>
   <dl>
    <dt><dfn class="css" data-dfn-for="column-fill" data-dfn-type="value" data-export id="valdef-column-fill-balance">balance<a class="self-link" href="#valdef-column-fill-balance"></a></dfn>
    <dd> Balance content equally between columns, as far as possible.
			In fragmented contexts, only the last fragment is balanced. 
    <dt><dfn class="css" data-dfn-for="column-fill" data-dfn-type="value" data-export id="valdef-column-fill-balance-all">balance-all<a class="self-link" href="#valdef-column-fill-balance-all"></a></dfn>
    <dd> Balance content equally between columns, as far as possible.
			In fragmented contexts, all fragments are balanced. 
    <dt><dfn class="css" data-dfn-for="column-fill" data-dfn-type="value" data-export id="valdef-column-fill-auto">auto<a class="self-link" href="#valdef-column-fill-auto"></a></dfn>
    <dd> fill columns sequentially 
   </dl>
   <p class="issue" id="issue-3ed47ce8"><a class="self-link" href="#issue-3ed47ce8"></a> We need to define the behavior of <span class="css">column-fill</span> in continuous contexts. A previous resolution (<a href="https://github.com/w3c/csswg-drafts/issues/3224#issuecomment-468089503">3224</a>) defined that the property should only be consulted if the length of columns was constrained in the block dimension. This was reverted in (<a href="https://github.com/w3c/csswg-drafts/issues/4036#issuecomment-531646703">4036</a>) pending further discussion.</p>
   <p>In continuous contexts, this property does not have any effect when there are overflow columns.</p>
   <div class="example" id="example-0143ee45">
    <a class="self-link" href="#example-0143ee45"></a> In this example, an article only has one short paragraph which fits on three lines. 
		The three lines are displayed in three different
		columns due to column balancing. 
<pre class="highlight"><c- f>article </c-><c- p>{</c->
  <c- k>width</c-><c- p>:</c-> <c- m>60</c-><c- l>em</c-><c- p>;</c->
  <c- k>height</c-><c- p>:</c-> auto<c- p>;</c->
  <c- k>columns</c-><c- p>:</c-> <c- m>4</c-><c- p>;</c->
  <c- k>column-fill</c-><c- p>:</c-> balance<c- p>;</c->
<c- p>}</c->
</pre>
    <figure>
      <img alt="Four columns, the first three have content." src="images/column-balancing-one-paragraph.svg"> 
     <figcaption>Three lines displayed in three columns due to column balancing.</figcaption>
    </figure>
   </div>
   <div class="example" id="example-8e97de73">
    <a class="self-link" href="#example-8e97de73"></a> In this example, column balancing is turned off, and the article has a height: 
<pre class="highlight"><c- f>article </c-><c- p>{</c->
  <c- k>width</c-><c- p>:</c-> <c- m>60</c-><c- l>em</c-><c- p>;</c->
  <c- k>height</c-><c- p>:</c-> <c- m>4</c-><c- l>em</c-><c- p>;</c->
  <c- k>columns</c-><c- p>:</c-> <c- m>4</c-><c- p>;</c->
  <c- k>column-fill</c-><c- p>:</c-> auto<c- p>;</c->
<c- p>}</c->
</pre>
    <p>As a result, the first column is filled with all content:</p>
    <figure>
      <img alt="Four columns, the first one has content." src="images/no-column-balancing-one-paragraph.svg"> 
     <figcaption>No balancing so the whole text is shown in one paragraph.</figcaption>
    </figure>
   </div>
   <div class="example" id="example-0c7abc2c">
    <a class="self-link" href="#example-0c7abc2c"></a> In this example, an article has two paragraphs: 
		first a long one, 
		then a shorter one. 
		This code is applied: 
<pre class="highlight"><c- f>article </c-><c- p>{</c->
  <c- k>width</c-><c- p>:</c-> <c- m>60</c-><c- l>em</c-><c- p>;</c->
  <c- k>height</c-><c- p>:</c-> auto<c- p>;</c->
  <c- k>columns</c-><c- p>:</c-> <c- m>4</c-><c- p>;</c->
  <c- k>column-fill</c-><c- p>:</c-> balance<c- p>;</c->
<c- p>}</c->

<c- f>p </c-><c- p>{</c->
  <c- k>break-after</c-><c- p>:</c-> column<c- p>;</c->
<c- p>}</c->
</pre>
    <p>The shortest column height possible contains five lines of text.
		After the column height has been established, columns are filled sequentially.
		As a result, the third column is as high as the first two columns,
		while the last column ends up being significantly shorter.</p>
    <figure>
      <img alt="Four columns, all have content." src="images/column-balancing-with-column-break.svg"> 
     <figcaption>Once column height is established, columns are filled sequentially.</figcaption>
    </figure>
   </div>
   <div class="example" id="example-3b949a54">
    <a class="self-link" href="#example-3b949a54"></a> 
<pre class="highlight"><c- f>article </c-><c- p>{</c->
  <c- k>width</c-><c- p>:</c-> <c- m>60</c-><c- l>em</c-><c- p>;</c->
  <c- k>height</c-><c- p>:</c-> auto<c- p>;</c->
  <c- k>columns</c-><c- p>:</c-> <c- m>4</c-><c- p>;</c->
  <c- k>column-fill</c-><c- p>:</c-> balance<c- p>;</c->
<c- p>}</c->
</pre>
    <p>In this example, an article starts with an unbreakable figure which sets the column height.
		Subsequent content is filled sequentially into the remaining columns:</p>
    <figure>
      <img alt="Column one contains an image, two and three have content." src="images/column-balancing-with-figure.svg"> 
     <figcaption>Column height is established by the figure.</figcaption>
    </figure>
   </div>
   <h2 class="heading settled" data-level="8" id="overflow"><span class="secno">8. </span><span class="content"> Overflow</span><a class="self-link" href="#overflow"></a></h2>
   <h3 class="heading settled" data-level="8.1" id="overflow-inside-multicol-elements"><span class="secno">8.1. </span><span class="content"> Overflow Inside Multicol Containers</span><a class="self-link" href="#overflow-inside-multicol-elements"></a></h3>
   <p>Except for cases where this would cause a column break,
	content that extends outside column boxes
	visibly overflows and is not clipped to the <a data-link-type="dfn" href="#column-box" id="ref-for-column-box⑥">column box</a>.</p>
   <p class="note" role="note"><span>Note:</span> See <a href="#column-breaks">§ 5 Column Breaks</a> for column breaks
	and <a href="#pagination-and-overflow-outside-multicol">§ 8.2 Pagination and Overflow Outside Multicol Containers</a> for whether it is clipped to the multi-column container’s content box.</p>
   <div class="example" id="example-276e0e20">
    <a class="self-link" href="#example-276e0e20"></a> In this example, the image is wider than the column: 
    <figure>
      <img alt="An imagine in the first column has visible overflow" src="images/image-overflow-not-clipped.svg"> 
     <figcaption>Content visibly overflows and is not clipped to the column box.</figcaption>
    </figure>
   </div>
   <h3 class="heading settled" data-level="8.2" id="pagination-and-overflow-outside-multicol"><span class="secno">8.2. </span><span class="content"> Pagination and Overflow Outside Multicol Containers</span><a class="self-link" href="#pagination-and-overflow-outside-multicol"></a></h3>
   <p>Content and column rules that extend outside column boxes at
	the edges of the multi-column container are clipped according to the <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-overflow-3/#propdef-overflow" id="ref-for-propdef-overflow">overflow</a> property.</p>
   <p>A multicol container can have more columns than it has room for due to:</p>
   <ul>
    <li> a declaration that constrains the column height 
			(e.g., using <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css2/visudet.html#propdef-height" id="ref-for-propdef-height">height</a> or <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css2/visudet.html#propdef-max-height" id="ref-for-propdef-max-height">max-height</a>). 
			In this case, additional column boxes are created in the inline direction 
    <li> the size of the page. 
			In this case, additional column boxes are moved to the next page(s). 
    <li> explicit column breaks. 
			In this case, additional column boxes are created in the inline direction for continuous contexts
			and additional column boxes are moved to the next fragment(s) for fragmented media. 
    <li>
   </ul>
   <p>Columns that appear outside the multicol container in continuous contexts
	are called <dfn data-dfn-type="dfn" data-export id="overflow-columns">overflow columns<a class="self-link" href="#overflow-columns"></a></dfn>. 
	Overflow columns can affect the height of the multicol container.</p>
   <div class="example" id="example-a5e26f6e">
    <a class="self-link" href="#example-a5e26f6e"></a> In this example, the height of the multi-column container has been constrained to a maximum height.
		Also, the style sheet specifies that overflowing content should be visible: 
<pre class="highlight"><c- f>div </c-><c- p>{</c->
  <c- k>max-height</c-><c- p>:</c-> <c- m>5</c-><c- l>em</c-><c- p>;</c->
  <c- k>overflow</c-><c- p>:</c-> visible<c- p>;</c->
<c- p>}</c->
</pre>
    <p>As a result, the number of columns is increased.</p>
    <figure>
      <img alt="Four columns, one outside the multicol container" src="images/height-constraint-overflow-inline.svg"> 
     <figcaption>An overflow column is created in the inline direction.</figcaption>
    </figure>
   </div>
   <div class="example" id="example-83d725a5">
    <a class="self-link" href="#example-83d725a5"></a> 
    <p>In continuous contexts overflow columns can affect the height of the multicol container.
		In this example a column appears in the overflow which has four lines of text. 
		The multicol container is made tall enough to accomodate this column.</p>
    <figure>
      <img alt="Four columns, overflow column is taller than the first three" src="images/overflow-column-effects-height.svg"> 
     <figcaption>The final column is an overflow column yet is taller than the others. 
			The container is tall enough for this column.</figcaption>
    </figure>
   </div>
   <div class="example" id="example-a048a782">
    <a class="self-link" href="#example-a048a782"></a> In fragmented contexts, the overflow content goes into columns in subsequent fragments.
		Given the same content as in example 31
		and a page box that only has room for five lines of formatted text,
		this would appear on the first page: 
    <figure>
      <img alt="Three columns" src="images/pagination-overflow-page1.svg"> 
     <figcaption>The first three paragraphs appear on page one.</figcaption>
    </figure>
    <p>Assuming column balancing, this would appear on the second page:</p>
    <figure>
      <img alt="Three columns" src="images/pagination-overflow-page2.svg"> 
     <figcaption>The overflow column is moved onto page two.</figcaption>
    </figure>
   </div>
   <div class="example" id="example-da1d960a">
    <a class="self-link" href="#example-da1d960a"></a> In this example, explicit column breaks are generated after paragraphs: 
<pre class="highlight"><c- f>p </c-><c- p>{</c->
  <c- k>break-after</c-><c- p>:</c-> column<c- p>;</c->
<c- p>}</c->
</pre>
    <p>As a result, the number of columns increases and the extra columns are added in the inline direction:</p>
    <figure>
      <img alt="Four columns, one outside the multicol container" src="images/height-constraint-column-break-overflow-inline.svg"> 
     <figcaption>An overflow column is created in the inline direction.</figcaption>
    </figure>
   </div>
   <div class="example" id="example-02cf1ca4">
    <a class="self-link" href="#example-02cf1ca4"></a> In paged media, extra columns are shown on the next page.
		Given the same code as the previous example,
		the last paragraph appears on the second page.
		This would appear on the first page: 
    <figure>
      <img alt="Three columns" src="images/pagination-column-break-overflow-page1.svg"> 
     <figcaption>The first three paragraphs appear on page one.</figcaption>
    </figure>
    <p>This would appear on the second page:</p>
    <figure>
      <img alt="Three columns" src="images/pagination-column-break-overflow-page2.svg"> 
     <figcaption>The overflow column is moved onto page two.</figcaption>
    </figure>
    <p>Due to column balancing, the last paragraph is split across three columns.</p>
   </div>
   <h2 class="no-num heading settled" id="changes"><span class="content">Appendix B. Changes</span><a class="self-link" href="#changes"></a></h2>
   <p>This appendix is <em>informative</em>.</p>
   <h3 class="heading settled" id="changes-from-20180528"><span class="content">Changes from the <a href="https://www.w3.org/TR/2018/WD-css-multicol-1-20180528/">Working Draft (WD) of 28 May 2018</a></span><a class="self-link" href="#changes-from-20180528"></a></h3>
   <ul>
    <li>Removed the non-normative text 
	"However, as described below, setting both the width and number of columns rarely makes sense." Editorial 16 Sep 2019, <a href="https://github.com/w3c/csswg-drafts/issues/4291">issue 4291</a>.
    <li>Added the paragraph, "Spanners are block-level boxes 
	therefore the margins of two adjacent spanners will collapse with each other.
	As column boxes establish a new <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#block-formatting-context" id="ref-for-block-formatting-context⑤">block formatting context</a>,
	margins on elements inside a column box will not collapse with the margin of a spanner." <a href="https://github.com/w3c/csswg-drafts/issues/2203#issuecomment-431783027">Resolved 22 Oct 2018</a>, see also the resolution for <a href="https://github.com/w3c/csswg-drafts/issues/2582#issuecomment-402619872">issue 2582</a>.
    <li>Clarified the spec to explain that a spanning element is taken out-of-flow, leaving a forced break. Added the paragraph, "A spanning element is taken out-of-flow, leaving a forced break. This does not affect the painting order of the spanning element." <a href="https://github.com/w3c/csswg-drafts/issues/1072#issuecomment-468087733">Resolved 28 Feb 2019</a>.
    <li>Moved the definition of the <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-align-3/#propdef-column-gap" id="ref-for-propdef-column-gap③">column-gap</a> property to <a data-link-type="biblio" href="#biblio-css3-align">[CSS3-ALIGN]</a> and added a paragraph detailing the specifics of <span class="property" id="ref-for-propdef-column-gap④">column-gap</span> in multicol: <br>"In a multi-column formatting context the used value of normal for the column-gap property is 1em. This ensures columns are readable when the initial values are used. If there is a column rule between columns, it will appear in the middle of the gap." <a href="https://github.com/w3c/csswg-drafts/issues/3641">Resolved 4 June 2019.</a>
    <li>Reworded the section <a href="#the-multi-column-model">The multi-column model</a>, based on input from Morten Stenshorne in <a href="https://github.com/w3c/csswg-drafts/issues/2203#issuecomment-431695940">issue 2203</a>.
    <li>Removed the at-risk marker from the length-percentage value for <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-align-3/#propdef-column-gap" id="ref-for-propdef-column-gap⑤">column-gap</a>. <a href="https://github.com/w3c/csswg-drafts/issues/3988">Resolved 4 June 2019.</a>
    <li>Updated the introduction to remove mention of the benefits of multicol over using tables for layout and instead refer to the unique characteristics of multicol. Editorial change referenced in <a href="https://github.com/w3c/csswg-drafts/issues/3654">issue 3654</a>.
    <li>Changed the sentence added in the pseudo-algorithm section after the 7 Jan 2016 resolution, to refer to <em>columns</em> and not <em>tracks</em> as tracks are not defined in this specification. Resolved <a href="https://github.com/w3c/csswg-drafts/issues/3649#issuecomment-472505520">13 March 2019</a>.
    <li>Changes and clarifications to the SVG images used in the specification.
   </ul>
   <h3 class="heading settled" id="changes-from-20171005"><span class="content">Changes from the <a href="https://www.w3.org/TR/2017/WD-css-multicol-1-20171005/">Working Draft (WD) of 5 October 2017</a></span><a class="self-link" href="#changes-from-20171005"></a></h3>
   <ul>
    <li>Changed references to paged media to refer to fragmented contexts. Resolved <a href="https://github.com/w3c/csswg-drafts/issues/1746#issuecomment-380731574">12 Apr 2018</a>.
    <li>Changed a line regarding the <code>column-fill</code> property: <br><q>In continuous media, this property does not have any effect in
	overflow columns.</q> <br>To: <br><q>In continuous media, this property does not have any effect when there are overflow columns.</q> <a href="https://github.com/w3c/csswg-drafts/issues/2549">Resolved: 12 Apr 2018</a>
    <li>Add a line of text plus an example to show that overflow columns can affect the multicol container height. <a href="https://github.com/w3c/csswg-drafts/issues/1745">Resolved: 12 Apr 2018</a>
    <li>Replaced the HTML mock-up examples with SVG versions, as the examples were unclear. <a href="https://github.com/w3c/csswg-drafts/issues/1087">Issue 1087</a>.
    <li>Changed the value of normal for column-gap to be 1em, rather than a UA-specified length with a suggestion of 1em. <a href="https://github.com/w3c/csswg-drafts/issues/2145#issuecomment-378781507">Resolved: 4 Apr 2018</a>
    <li>Clarified that negative values are not allowed for column-width, and that while 0 may be specified, used values will be clamped to a minimum of 1px. <a href="https://github.com/w3c/csswg-drafts/issues/1741#issuecomment-373091628">Resolved: 14 Mar 2018</a>
    <li>Clarified that where there is a spanning element content is automatically balanced across all columns in the immediately preceding column row before the element appears. <a href="https://github.com/w3c/csswg-drafts/issues/1075">Resolved: 9 Nov 2017</a>
    <li>Added clarification plus an additional example that spanning elements may be lower the the first level of descendents, and that in the case of margins, borders and padding on the element containing the spanning, this would be drawn above the spanner. <a href="https://github.com/w3c/csswg-drafts/issues/1072#issuecomment-342668025">Resolved: 8 Nov 2017</a>
    <li>Changed the sentence <q>Column rules are painted in the inline content layer, but below all inline content inside the multicol element.</q> to <q>Column rules are painted just above the border of the multicol element. For scrollable multicol elements, note that while the border and background of the multicol element obviously aren’t scrolled, the rules need to scroll along with the columns.</q> <a href="https://github.com/w3c/csswg-drafts/issues/1739#issuecomment-342659978">Resolved: 7 Nov 2017</a>
    <li>Under section The Multi-column Model, removed two sentences <q>That is, column boxes behave like block-level, table cell, and inline-block boxes as per CSS 2.1, section 10.1, item 2 CSS21. However, column boxes do not establish block container boxes for elements with <a class="css" data-link-type="propdesc" href="https://drafts.csswg.org/css-position-3/#propdef-position" id="ref-for-propdef-position③">position: fixed or position: absolute</a>.</q>. THese were replaced with a clarification about the principal box and a new example showing how abspos elements refer to the multicol container. <a href="https://github.com/w3c/csswg-drafts/issues/1738#issuecomment-342661881">Resolved: 7 Nov 2017</a>
    <li>Removed the sentence "To indicate where column breaks should (or should not) appear, new keyword values are introduced." and following example (Example 7 in the WD published <a href="https://www.w3.org/TR/2017/WD-css-multicol-1-20171005/">5 Oct 2017</a>) as the multicol specification no longer introduces these properties. <a href="https://github.com/w3c/csswg-drafts/issues/1966">Editorial</a>
    <li>Changed how we reference the element we have applied multicol to from multi-column or multicol <q>element</q> to multi-column or multicol <q>container</q>. <a href="https://github.com/w3c/csswg-drafts/issues/1965">Resolved: 22 November 2017</a>
    <li>Removed the example which stated "If a tall image is moved to a column on the next page to find room for it, its natural column may be left empty. If so, the column is still considered to have content for the purpose of deciding if the column rule should be drawn." <a href="https://github.com/w3c/csswg-drafts/issues/1740">Resolved: 7 September 2017</a>
   </ul>
   <h3 class="heading settled" id="changes-from-20110412"><span class="content">Changes from the <a href="https://www.w3.org/TR/2011/CR-css3-multicol-20110412/">Candidate Recommendation (CR) of 12 April 2011</a>.</span><a class="self-link" href="#changes-from-20110412"></a></h3>
   <ul>
    <li>Added July 2016 resolution to change the the track size floor to a required UA-specified value, consistent with the CSS Grid spec. <a href="https://lists.w3.org/Archives/Public/www-style/2016Jan/0031.html">Resolved: 7 Jan 2016</a> 
    <li>Remove the restriction about overflow columns only being in continuous media in the statement that <a class="property" data-link-type="propdesc" href="#propdef-column-fill" id="ref-for-propdef-column-fill②">column-fill</a> has no effect on overflow columns. <a href="https://lists.w3.org/Archives/Public/www-style/2013Sep/0471.html">Resolved: September 2013</a>. 
    <li>Added keyword balance-all and examples to demonstrate how this should work. <a href="https://lists.w3.org/Archives/Public/www-style/2013Sep/0471.html">Resolved: September 2013</a>. 
    <li> The pseudo-algorithm has been revised on a number of occasions. <a href="https://lists.w3.org/Archives/Public/www-style/2013Feb/0471.html">Latest change Feb 2013</a>. 
    <li>Clarified that properties <a class="property" data-link-type="propdesc" href="#propdef-columns" id="ref-for-propdef-columns④">columns</a>, <a class="property" data-link-type="propdesc" href="#propdef-column-width" id="ref-for-propdef-column-width①③">column-width</a>, <a class="property" data-link-type="propdesc" href="#propdef-column-count" id="ref-for-propdef-column-count①②">column-count</a> "apply to block containers". <a href="https://lists.w3.org/Archives/Public/www-style/2013Feb/0536.html">Ref: Feb 2013</a>. 
    <li>Breaking properties have beeen moved from this specification to the <a href="https://www.w3.org/TR/css-break-3/">CSS Fragmentation Module</a>. 
    <li>Change to <a class="property" data-link-type="propdesc" href="#propdef-column-fill" id="ref-for-propdef-column-fill③">column-fill</a> wording to clarify that <span class="property" id="ref-for-propdef-column-fill④">column-fill</span> is honored before page breaks. <a href="https://lists.w3.org/Archives/Public/www-style/2012Jan/0393.html">Ref: Jan 2012</a>. 
    <li>Amended example and text to clarify what happens with margin collapsing and spanning elements. <a href="https://lists.w3.org/Archives/Public/www-style/2013Oct/0247.html">Ref: Oct 2013</a>. 
    <li>Clarification that <a class="property" data-link-type="propdesc" href="#propdef-column-rule-width" id="ref-for-propdef-column-rule-width④">column-rule-width</a> does not alter the size or placement of columns. <a href="https://lists.w3.org/Archives/Public/www-style/2013Sep/0550.html">Ref: Sep 2013</a>. 
    <li>Added that each column spanning element establishes a separate BFC margins between them collapse. <a href="https://lists.w3.org/Archives/Public/www-style/2011Dec/0262.html">Ref: Dec 2011</a>. 
    <li>Column rules are painted in the inline content layer, but below all inline content inside the multicol. <a href="https://lists.w3.org/Archives/Public/www-style/2013Feb/0363.html">Ref: Feb 2013</a>. 
    <li>Clarify that <a class="property" data-link-type="propdesc" href="#propdef-column-span" id="ref-for-propdef-column-span⑦">column-span</a> causes the element to establish a formatting context even if it is not in a multicol. 
    <li>Column spanners do not always establish a <em>block</em> formatting context. 
    <li>Allow <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-align-3/#propdef-column-gap" id="ref-for-propdef-column-gap⑥">column-gap</a> to accept <a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-4/#typedef-length-percentage" id="ref-for-typedef-length-percentage">&lt;length-percentage></a> instead of just <a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-3/#length-value" id="ref-for-length-value②" title="Expands to: em | vb | ch | cm | vh | vi | in | ex | vw | ic | pt | px | lh | pc | rem | rlh | vmax | advance measure | vmin | mm | cap | q">&lt;length></a> 
    <li><a class="property" data-link-type="propdesc" href="#propdef-column-width" id="ref-for-propdef-column-width①④">column-width</a> and <a class="property" data-link-type="propdesc" href="#propdef-column-count" id="ref-for-propdef-column-count①③">column-count</a> applies to <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#block-container" id="ref-for-block-container③">block containers</a> except <a data-link-type="dfn" href="https://drafts.csswg.org/css-tables-3/#table-wrapper-box" id="ref-for-table-wrapper-box②">table wrapper boxes</a>. 
    <li>Content that overflows columns is not clipped. 
   </ul>
   <h2 class="no-num heading settled" id="acknowledgments"><span class="content"> Acknowledgments</span><a class="self-link" href="#acknowledgments"></a></h2>
   <p>This document is based on several older proposals and comments on older proposals.
	Contributors include:</p>
   <p>Alex Mogilevsky,
	Andy Clarke,
	Anton Prowse,
	Bert Bos,
	Björn Höhrmann,
	Cédric Savarese,
	Chris Lilley,
	Chris Wilson,
	Daniel Glazman and
	Dave Raggett,
	David Hyatt,
	David Singer,
	David Woolley,
	Elika Etemad,
	Giovanni Campagna,
	Ian Hickson.
	Joost de Valk,
	Kevin Lawver,
	L. David Baron,
	Markus Mielke,
	Melinda Grant,
	Michael Day,
	Morten Stenshorne,
	Øyvind Stenhaug,
	Peter Linss,
	Peter-Paul Koch,
	Robert O’Callahan,
	Robert Stevahn,
	Sergey Genkin,
	Shelby Moore,
	Steve Zilles,
	Sylvain Galineau,
	Tantek Çelik,
	Till Halbach,</p>
   <p></p>
  </main>
  <h2 class="no-ref no-num heading settled" id="conformance"><span class="content"> Conformance</span><a class="self-link" href="#conformance"></a></h2>
  <h3 class="heading settled" id="document-conventions"><span class="content"> Document conventions</span><a class="self-link" href="#document-conventions"></a></h3>
  <p>Conformance requirements are expressed with a combination of
	descriptive assertions and RFC 2119 terminology. The key words “MUST”,
	“MUST NOT”, “REQUIRED”, “SHALL”, “SHALL NOT”, “SHOULD”, “SHOULD NOT”,
	“RECOMMENDED”, “MAY”, and “OPTIONAL” in the normative parts of this
	document are to be interpreted as described in RFC 2119.
	However, for readability, these words do not appear in all uppercase
	letters in this specification. </p>
  <p>All of the text of this specification is normative except sections
	explicitly marked as non-normative, examples, and notes. <a data-link-type="biblio" href="#biblio-rfc2119">[RFC2119]</a> </p>
  <p>Examples in this specification are introduced with the words “for example”
	or are set apart from the normative text with <code>class="example"</code>,
	like this: </p>
  <div class="example" id="example-ae2b6bc0">
   <a class="self-link" href="#example-ae2b6bc0"></a> 
   <p>This is an example of an informative example. </p>
  </div>
  <p>Informative notes begin with the word “Note” and are set apart from the
	normative text with <code>class="note"</code>, like this: </p>
  <p class="note" role="note">Note, this is an informative note. </p>
  <p>Advisements are normative sections styled to evoke special attention and are
	set apart from other normative text with <code>&lt;strong class="advisement"></code>, like
	this: <strong class="advisement"> UAs MUST provide an accessible alternative. </strong> </p>
  <h3 class="heading settled" id="conform-classes"><span class="content"> Conformance classes</span><a class="self-link" href="#conform-classes"></a></h3>
  <p>Conformance to this specification
	is defined for three conformance classes: </p>
  <dl>
   <dt>style sheet 
   <dd>A <a href="http://www.w3.org/TR/CSS2/conform.html#style-sheet">CSS
			style sheet</a>. 
   <dt>renderer 
   <dd>A <a href="http://www.w3.org/TR/CSS2/conform.html#user-agent">UA</a> that interprets the semantics of a style sheet and renders
			documents that use them. 
   <dt>authoring tool 
   <dd>A <a href="http://www.w3.org/TR/CSS2/conform.html#user-agent">UA</a> that writes a style sheet. 
  </dl>
  <p>A style sheet is conformant to this specification
	if all of its statements that use syntax defined in this module are valid
	according to the generic CSS grammar and the individual grammars of each
	feature defined in this module. </p>
  <p>A renderer is conformant to this specification
	if, in addition to interpreting the style sheet as defined by the
	appropriate specifications, it supports all the features defined
	by this specification by parsing them correctly
	and rendering the document accordingly. However, the inability of a
	UA to correctly render a document due to limitations of the device
	does not make the UA non-conformant. (For example, a UA is not
	required to render color on a monochrome monitor.) </p>
  <p>An authoring tool is conformant to this specification
	if it writes style sheets that are syntactically correct according to the
	generic CSS grammar and the individual grammars of each feature in
	this module, and meet all other conformance requirements of style sheets
	as described in this module. </p>
  <h3 class="heading settled" id="conform-responsible"><span class="content"> Requirements for Responsible Implementation of CSS</span><a class="self-link" href="#conform-responsible"></a></h3>
  <p>The following sections define several conformance requirements
		for implementing CSS responsibly,
		in a way that promotes interoperability in the present and future. </p>
  <h4 class="heading settled" id="conform-partial"><span class="content"> Partial Implementations</span><a class="self-link" href="#conform-partial"></a></h4>
  <p>So that authors can exploit the forward-compatible parsing rules to assign fallback values, <strong>CSS renderers <em>must</em> treat as invalid
		(and <a href="http://www.w3.org/TR/CSS2/conform.html#ignore">ignore as appropriate</a>)
		any at-rules, properties, property values, keywords, and other syntactic constructs
		for which they have no usable level of support</strong>.
		In particular, user agents <em>must not</em> selectively ignore
		unsupported property values and honor supported values in a single multi-value property declaration:
		if any value is considered invalid (as unsupported values must be),
		CSS requires that the entire declaration be ignored. </p>
  <h4 class="heading settled" id="conform-future-proofing"><span class="content"> Implementations of Unstable and Proprietary Features</span><a class="self-link" href="#conform-future-proofing"></a></h4>
  <p>To avoid clashes with future stable CSS features,
		the CSSWG recommends <a href="http://www.w3.org/TR/CSS/#future-proofing">following best practices</a> for the implementation of <a href="http://www.w3.org/TR/CSS/#unstable">unstable</a> features and <a href="http://www.w3.org/TR/CSS/#proprietary-extension">proprietary extensions</a> to CSS. </p>
  <h4 class="heading settled" id="conform-testing"><span class="content"> Implementations of CR-level Features</span><a class="self-link" href="#conform-testing"></a></h4>
  <p>Once a specification reaches the Candidate Recommendation stage,
		implementers should release an <a data-link-type="dfn" href="http://www.w3.org/TR/CSS/#vendor-prefix">unprefixed</a> implementation
		of any CR-level feature they can demonstrate
		to be correctly implemented according to spec,
		and should avoid exposing a prefixed variant of that feature. </p>
  <p>To establish and maintain the interoperability of CSS across
		implementations, the CSS Working Group requests that non-experimental
		CSS renderers submit an implementation report (and, if necessary, the
		testcases used for that implementation report) to the W3C before
		releasing an unprefixed implementation of any CSS features. Testcases
		submitted to W3C are subject to review and correction by the CSS
		Working Group. </p>
  <p>
   Further information on submitting testcases and implementation reports
		can be found from on the CSS Working Group’s website at <a href="http://www.w3.org/Style/CSS/Test/">http://www.w3.org/Style/CSS/Test/</a>.
		Questions should be directed to the <a href="http://lists.w3.org/Archives/Public/public-css-testsuite">public-css-testsuite@w3.org</a> mailing list. 
<script src="https://www.w3.org/scripts/TR/2016/fixup.js"></script>
  </p>
  <h2 class="no-num no-ref heading settled" id="index"><span class="content">Index</span><a class="self-link" href="#index"></a></h2>
  <h3 class="no-num no-ref heading settled" id="index-defined-here"><span class="content">Terms defined by this specification</span><a class="self-link" href="#index-defined-here"></a></h3>
  <ul class="index">
   <li><a href="#valdef-column-span-all">all</a><span>, in §6.1</span>
   <li>
    auto
    <ul>
     <li><a href="#valdef-column-count-auto">value for column-count</a><span>, in §3.2</span>
     <li><a href="#valdef-column-fill-auto">value for column-fill</a><span>, in §7.1</span>
     <li><a href="#valdef-column-width-auto">value for column-width</a><span>, in §3.1</span>
    </ul>
   <li><a href="#valdef-column-fill-balance">balance</a><span>, in §7.1</span>
   <li><a href="#valdef-column-fill-balance-all">balance-all</a><span>, in §7.1</span>
   <li><a href="#valdef-column-rule-color-color">&lt;color></a><span>, in §4.2</span>
   <li><a href="#column-box">column</a><span>, in §2</span>
   <li><a href="#column-box">column box</a><span>, in §2</span>
   <li><a href="#propdef-column-count">column-count</a><span>, in §3.2</span>
   <li><a href="#propdef-column-fill">column-fill</a><span>, in §7.1</span>
   <li><a href="#column-gap">column gap</a><span>, in §2</span>
   <li><a href="#column-height">column height</a><span>, in §2</span>
   <li><a href="#propdef-column-rule">column-rule</a><span>, in §4.5</span>
   <li><a href="#column-rule">column rule</a><span>, in §2</span>
   <li><a href="#propdef-column-rule-color">column-rule-color</a><span>, in §4.2</span>
   <li><a href="#propdef-column-rule-style">column-rule-style</a><span>, in §4.3</span>
   <li><a href="#propdef-column-rule-width">column-rule-width</a><span>, in §4.4</span>
   <li><a href="#propdef-columns">columns</a><span>, in §3.3</span>
   <li><a href="#propdef-column-span">column-span</a><span>, in §6.1</span>
   <li><a href="#propdef-column-width">column-width</a><span>, in §3.1</span>
   <li><a href="#column-width">column width</a><span>, in §2</span>
   <li><a href="#valdef-column-count-integer">&lt;integer></a><span>, in §3.2</span>
   <li><a href="#valdef-column-width-length">&lt;length></a><span>, in §3.1</span>
   <li><a href="#multi-column-container">multicol container</a><span>, in §2</span>
   <li><a href="#multi-column-line">multi-col line</a><span>, in §2</span>
   <li><a href="#multi-column-line">multicol line</a><span>, in §2</span>
   <li><a href="#multi-column-container">multi-column container</a><span>, in §2</span>
   <li><a href="#multi-column-formatting-context">multi-column formatting context</a><span>, in §2</span>
   <li><a href="#multi-column-layout">multi-column layout</a><span>, in §1</span>
   <li><a href="#multi-column-line">multi-column line</a><span>, in §2</span>
   <li><a href="#valdef-column-span-none">none</a><span>, in §6.1</span>
   <li><a href="#overflow-columns">overflow columns</a><span>, in §8.2</span>
   <li><a href="#spanner">spanner</a><span>, in §6.1</span>
   <li><a href="#spanning-element">spanning element</a><span>, in §6.1</span>
  </ul>
  <aside class="dfn-panel" data-for="term-for-typedef-line-style">
   <a href="https://drafts.csswg.org/css-backgrounds-3/#typedef-line-style">https://drafts.csswg.org/css-backgrounds-3/#typedef-line-style</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-typedef-line-style">4.3. The Style Of Column Rules: the column-rule-style property</a> <a href="#ref-for-typedef-line-style①">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-typedef-line-width">
   <a href="https://drafts.csswg.org/css-backgrounds-3/#typedef-line-width">https://drafts.csswg.org/css-backgrounds-3/#typedef-line-width</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-typedef-line-width">4.4. The Width Of Column Rules: the column-rule-width property</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-propdef-border">
   <a href="https://drafts.csswg.org/css-backgrounds-3/#propdef-border">https://drafts.csswg.org/css-backgrounds-3/#propdef-border</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-border">1. 
Introduction</a> <a href="#ref-for-propdef-border①">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-valdef-line-style-hidden">
   <a href="https://drafts.csswg.org/css-backgrounds-3/#valdef-line-style-hidden">https://drafts.csswg.org/css-backgrounds-3/#valdef-line-style-hidden</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-valdef-line-style-hidden">4.4. The Width Of Column Rules: the column-rule-width property</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-valdef-line-style-none">
   <a href="https://drafts.csswg.org/css-backgrounds-3/#valdef-line-style-none">https://drafts.csswg.org/css-backgrounds-3/#valdef-line-style-none</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-valdef-line-style-none">4.3. The Style Of Column Rules: the column-rule-style property</a>
    <li><a href="#ref-for-valdef-line-style-none①">4.4. The Width Of Column Rules: the column-rule-width property</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-fragment">
   <a href="https://drafts.csswg.org/css-break-4/#fragment">https://drafts.csswg.org/css-break-4/#fragment</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-fragment">2. 
The Multi-Column Model</a>
    <li><a href="#ref-for-fragment①">6.1. Spanning An Element Across Columns: the column-span property</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-fragmentation">
   <a href="https://drafts.csswg.org/css-break-4/#fragmentation">https://drafts.csswg.org/css-break-4/#fragmentation</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-fragmentation">2. 
The Multi-Column Model</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-fragmentation-container">
   <a href="https://drafts.csswg.org/css-break-4/#fragmentation-container">https://drafts.csswg.org/css-break-4/#fragmentation-container</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-fragmentation-container">2. 
The Multi-Column Model</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-fragmentation-context">
   <a href="https://drafts.csswg.org/css-break-4/#fragmentation-context">https://drafts.csswg.org/css-break-4/#fragmentation-context</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-fragmentation-context">2. 
The Multi-Column Model</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-propdef-widows">
   <a href="https://drafts.csswg.org/css-break-4/#propdef-widows">https://drafts.csswg.org/css-break-4/#propdef-widows</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-widows">7. 
Filling Columns</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-valuea-def-color">
   <a href="https://drafts.csswg.org/css-color-3/#valuea-def-color">https://drafts.csswg.org/css-color-3/#valuea-def-color</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-valuea-def-color">4.2. The Color of Column Rules: the 
column-rule-color property</a> <a href="#ref-for-valuea-def-color①">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-absolutely-positioned">
   <a href="https://drafts.csswg.org/css-display-3/#absolutely-positioned">https://drafts.csswg.org/css-display-3/#absolutely-positioned</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-absolutely-positioned">2. 
The Multi-Column Model</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-anonymous">
   <a href="https://drafts.csswg.org/css-display-3/#anonymous">https://drafts.csswg.org/css-display-3/#anonymous</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-anonymous">2. 
The Multi-Column Model</a> <a href="#ref-for-anonymous①">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-block-container">
   <a href="https://drafts.csswg.org/css-display-3/#block-container">https://drafts.csswg.org/css-display-3/#block-container</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-block-container">2. 
The Multi-Column Model</a>
    <li><a href="#ref-for-block-container①">3.1. The Inline Size of Columns: the column-width property</a>
    <li><a href="#ref-for-block-container②">3.2. The Number of Columns: the column-count property</a>
    <li><a href="#ref-for-block-container③">Changes from the
Candidate Recommendation (CR) of 12 April 2011.</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-block-formatting-context">
   <a href="https://drafts.csswg.org/css-display-3/#block-formatting-context">https://drafts.csswg.org/css-display-3/#block-formatting-context</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-block-formatting-context">2. 
The Multi-Column Model</a> <a href="#ref-for-block-formatting-context①">(2)</a> <a href="#ref-for-block-formatting-context②">(3)</a>
    <li><a href="#ref-for-block-formatting-context③">6.1. Spanning An Element Across Columns: the column-span property</a> <a href="#ref-for-block-formatting-context④">(2)</a>
    <li><a href="#ref-for-block-formatting-context⑤">Changes from the Working Draft (WD) of 28 May 2018</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-block-level-box">
   <a href="https://drafts.csswg.org/css-display-3/#block-level-box">https://drafts.csswg.org/css-display-3/#block-level-box</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-block-level-box">2. 
The Multi-Column Model</a> <a href="#ref-for-block-level-box①">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-containing-block">
   <a href="https://drafts.csswg.org/css-display-3/#containing-block">https://drafts.csswg.org/css-display-3/#containing-block</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-containing-block">2. 
The Multi-Column Model</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-propdef-display">
   <a href="https://drafts.csswg.org/css-display-3/#propdef-display">https://drafts.csswg.org/css-display-3/#propdef-display</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-display">2. 
The Multi-Column Model</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-formatting-context">
   <a href="https://drafts.csswg.org/css-display-3/#formatting-context">https://drafts.csswg.org/css-display-3/#formatting-context</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-formatting-context">6.1. Spanning An Element Across Columns: the column-span property</a> <a href="#ref-for-formatting-context①">(2)</a> <a href="#ref-for-formatting-context②">(3)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-independent-formatting-context">
   <a href="https://drafts.csswg.org/css-display-3/#independent-formatting-context">https://drafts.csswg.org/css-display-3/#independent-formatting-context</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-independent-formatting-context">2. 
The Multi-Column Model</a> <a href="#ref-for-independent-formatting-context①">(2)</a>
    <li><a href="#ref-for-independent-formatting-context②">6.1. Spanning An Element Across Columns: the column-span property</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-out-of-flow">
   <a href="https://drafts.csswg.org/css-display-3/#out-of-flow">https://drafts.csswg.org/css-display-3/#out-of-flow</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-out-of-flow">6.1. Spanning An Element Across Columns: the column-span property</a> <a href="#ref-for-out-of-flow①">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-principal-box">
   <a href="https://drafts.csswg.org/css-display-3/#principal-box">https://drafts.csswg.org/css-display-3/#principal-box</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-principal-box">2. 
The Multi-Column Model</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-grid-container">
   <a href="https://drafts.csswg.org/css-grid-1/#grid-container">https://drafts.csswg.org/css-grid-1/#grid-container</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-grid-container">1. 
Introduction</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-grid-item">
   <a href="https://drafts.csswg.org/css-grid-1/#grid-item">https://drafts.csswg.org/css-grid-1/#grid-item</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-grid-item">1. 
Introduction</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-propdef-overflow">
   <a href="https://drafts.csswg.org/css-overflow-3/#propdef-overflow">https://drafts.csswg.org/css-overflow-3/#propdef-overflow</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-overflow">8.2. 
Pagination and Overflow Outside Multicol Containers</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-propdef-position">
   <a href="https://drafts.csswg.org/css-position-3/#propdef-position">https://drafts.csswg.org/css-position-3/#propdef-position</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-position">2. 
The Multi-Column Model</a> <a href="#ref-for-propdef-position①">(2)</a> <a href="#ref-for-propdef-position②">(3)</a>
    <li><a href="#ref-for-propdef-position③">Changes from the Working Draft (WD) of 5 October 2017</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-table-wrapper-box">
   <a href="https://drafts.csswg.org/css-tables-3/#table-wrapper-box">https://drafts.csswg.org/css-tables-3/#table-wrapper-box</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-table-wrapper-box">3.1. The Inline Size of Columns: the column-width property</a>
    <li><a href="#ref-for-table-wrapper-box①">3.2. The Number of Columns: the column-count property</a>
    <li><a href="#ref-for-table-wrapper-box②">Changes from the
Candidate Recommendation (CR) of 12 April 2011.</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-integer-value">
   <a href="https://drafts.csswg.org/css-values-3/#integer-value">https://drafts.csswg.org/css-values-3/#integer-value</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-integer-value">3.2. The Number of Columns: the column-count property</a> <a href="#ref-for-integer-value①">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-length-value">
   <a href="https://drafts.csswg.org/css-values-3/#length-value">https://drafts.csswg.org/css-values-3/#length-value</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-length-value">3.1. The Inline Size of Columns: the column-width property</a> <a href="#ref-for-length-value①">(2)</a>
    <li><a href="#ref-for-length-value②">Changes from the
Candidate Recommendation (CR) of 12 April 2011.</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-typedef-length-percentage">
   <a href="https://drafts.csswg.org/css-values-4/#typedef-length-percentage">https://drafts.csswg.org/css-values-4/#typedef-length-percentage</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-typedef-length-percentage">Changes from the
Candidate Recommendation (CR) of 12 April 2011.</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-comb-one">
   <a href="https://drafts.csswg.org/css-values-4/#comb-one">https://drafts.csswg.org/css-values-4/#comb-one</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-comb-one">3.1. The Inline Size of Columns: the column-width property</a>
    <li><a href="#ref-for-comb-one①">3.2. The Number of Columns: the column-count property</a>
    <li><a href="#ref-for-comb-one②">6.1. Spanning An Element Across Columns: the column-span property</a>
    <li><a href="#ref-for-comb-one③">7.1. Column Balancing: the column-fill property</a> <a href="#ref-for-comb-one④">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-comb-any">
   <a href="https://drafts.csswg.org/css-values-4/#comb-any">https://drafts.csswg.org/css-values-4/#comb-any</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-comb-any">3.3. The column-width and column-count Shorthand: The columns Property</a>
    <li><a href="#ref-for-comb-any①">4.5. Column Rule Shorthand: the column-rule property</a> <a href="#ref-for-comb-any②">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-block-axis">
   <a href="https://drafts.csswg.org/css-writing-modes-4/#block-axis">https://drafts.csswg.org/css-writing-modes-4/#block-axis</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-block-axis">2. 
The Multi-Column Model</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-inline-base-direction">
   <a href="https://drafts.csswg.org/css-writing-modes-4/#inline-base-direction">https://drafts.csswg.org/css-writing-modes-4/#inline-base-direction</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-inline-base-direction">2. 
The Multi-Column Model</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-propdef-height">
   <a href="https://drafts.csswg.org/css2/visudet.html#propdef-height">https://drafts.csswg.org/css2/visudet.html#propdef-height</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-height">8.2. 
Pagination and Overflow Outside Multicol Containers</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-propdef-max-height">
   <a href="https://drafts.csswg.org/css2/visudet.html#propdef-max-height">https://drafts.csswg.org/css2/visudet.html#propdef-max-height</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-max-height">8.2. 
Pagination and Overflow Outside Multicol Containers</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-propdef-width">
   <a href="https://drafts.csswg.org/css2/visudet.html#propdef-width">https://drafts.csswg.org/css2/visudet.html#propdef-width</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-width">2. 
The Multi-Column Model</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-propdef-column-gap">
   <a href="https://drafts.csswg.org/css-align-3/#propdef-column-gap">https://drafts.csswg.org/css-align-3/#propdef-column-gap</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-column-gap">4.1. Gutters Between Columns: the column-gap property</a> <a href="#ref-for-propdef-column-gap①">(2)</a> <a href="#ref-for-propdef-column-gap②">(3)</a>
    <li><a href="#ref-for-propdef-column-gap③">Changes from the Working Draft (WD) of 28 May 2018</a> <a href="#ref-for-propdef-column-gap④">(2)</a> <a href="#ref-for-propdef-column-gap⑤">(3)</a>
    <li><a href="#ref-for-propdef-column-gap⑥">Changes from the
Candidate Recommendation (CR) of 12 April 2011.</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-valdef-row-gap-normal">
   <a href="https://drafts.csswg.org/css-align-3/#valdef-row-gap-normal">https://drafts.csswg.org/css-align-3/#valdef-row-gap-normal</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-valdef-row-gap-normal">4.1. Gutters Between Columns: the column-gap property</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-propdef-break-after">
   <a href="https://drafts.csswg.org/css-break-3/#propdef-break-after">https://drafts.csswg.org/css-break-3/#propdef-break-after</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-break-after">5. 
Column Breaks</a>
    <li><a href="#ref-for-propdef-break-after①">5.1. Controlling Fragmentation: the break-before, break-after, break-inside properties</a> <a href="#ref-for-propdef-break-after②">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-propdef-break-before">
   <a href="https://drafts.csswg.org/css-break-3/#propdef-break-before">https://drafts.csswg.org/css-break-3/#propdef-break-before</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-break-before">5. 
Column Breaks</a>
    <li><a href="#ref-for-propdef-break-before①">5.1. Controlling Fragmentation: the break-before, break-after, break-inside properties</a> <a href="#ref-for-propdef-break-before②">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-propdef-break-inside">
   <a href="https://drafts.csswg.org/css-break-3/#propdef-break-inside">https://drafts.csswg.org/css-break-3/#propdef-break-inside</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-break-inside">5. 
Column Breaks</a>
    <li><a href="#ref-for-propdef-break-inside①">5.1. Controlling Fragmentation: the break-before, break-after, break-inside properties</a> <a href="#ref-for-propdef-break-inside②">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-propdef-orphans">
   <a href="https://drafts.csswg.org/css-break-3/#propdef-orphans">https://drafts.csswg.org/css-break-3/#propdef-orphans</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-orphans">7. 
Filling Columns</a>
   </ul>
  </aside>
  <h3 class="no-num no-ref heading settled" id="index-defined-elsewhere"><span class="content">Terms defined by reference</span><a class="self-link" href="#index-defined-elsewhere"></a></h3>
  <ul class="index">
   <li>
    <a data-link-type="biblio">[css-backgrounds-3]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-typedef-line-style" style="color:initial">&lt;line-style></span>
     <li><span class="dfn-paneled" id="term-for-typedef-line-width" style="color:initial">&lt;line-width></span>
     <li><span class="dfn-paneled" id="term-for-propdef-border" style="color:initial">border</span>
     <li><span class="dfn-paneled" id="term-for-valdef-line-style-hidden" style="color:initial">hidden</span>
     <li><span class="dfn-paneled" id="term-for-valdef-line-style-none" style="color:initial">none</span>
    </ul>
   <li>
    <a data-link-type="biblio">[css-break-4]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-fragment" style="color:initial">fragment</span>
     <li><span class="dfn-paneled" id="term-for-fragmentation" style="color:initial">fragmentation</span>
     <li><span class="dfn-paneled" id="term-for-fragmentation-container" style="color:initial">fragmentation container</span>
     <li><span class="dfn-paneled" id="term-for-fragmentation-context" style="color:initial">fragmentation context</span>
     <li><span class="dfn-paneled" id="term-for-propdef-widows" style="color:initial">widows</span>
    </ul>
   <li>
    <a data-link-type="biblio">[css-color-3]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-valuea-def-color" style="color:initial">&lt;color></span>
    </ul>
   <li>
    <a data-link-type="biblio">[css-display-3]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-absolutely-positioned" style="color:initial">absolutely positioned box</span>
     <li><span class="dfn-paneled" id="term-for-anonymous" style="color:initial">anonymous box</span>
     <li><span class="dfn-paneled" id="term-for-block-container" style="color:initial">block container</span>
     <li><span class="dfn-paneled" id="term-for-block-formatting-context" style="color:initial">block formatting context</span>
     <li><span class="dfn-paneled" id="term-for-block-level-box" style="color:initial">block-level box</span>
     <li><span class="dfn-paneled" id="term-for-containing-block" style="color:initial">containing block</span>
     <li><span class="dfn-paneled" id="term-for-propdef-display" style="color:initial">display</span>
     <li><span class="dfn-paneled" id="term-for-formatting-context" style="color:initial">formatting context</span>
     <li><span class="dfn-paneled" id="term-for-independent-formatting-context" style="color:initial">independent formatting context</span>
     <li><span class="dfn-paneled" id="term-for-out-of-flow" style="color:initial">out-of-flow</span>
     <li><span class="dfn-paneled" id="term-for-principal-box" style="color:initial">principal box</span>
    </ul>
   <li>
    <a data-link-type="biblio">[css-grid-1]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-grid-container" style="color:initial">grid container</span>
     <li><span class="dfn-paneled" id="term-for-grid-item" style="color:initial">grid item</span>
    </ul>
   <li>
    <a data-link-type="biblio">[css-overflow-3]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-propdef-overflow" style="color:initial">overflow</span>
    </ul>
   <li>
    <a data-link-type="biblio">[css-position-3]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-propdef-position" style="color:initial">position</span>
    </ul>
   <li>
    <a data-link-type="biblio">[css-tables-3]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-table-wrapper-box" style="color:initial">table wrapper box</span>
    </ul>
   <li>
    <a data-link-type="biblio">[css-values-3]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-integer-value" style="color:initial">&lt;integer></span>
     <li><span class="dfn-paneled" id="term-for-length-value" style="color:initial">&lt;length></span>
    </ul>
   <li>
    <a data-link-type="biblio">[css-values-4]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-typedef-length-percentage" style="color:initial">&lt;length-percentage></span>
     <li><span class="dfn-paneled" id="term-for-comb-one" style="color:initial">|</span>
     <li><span class="dfn-paneled" id="term-for-comb-any" style="color:initial">||</span>
    </ul>
   <li>
    <a data-link-type="biblio">[css-writing-modes-4]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-block-axis" style="color:initial">block axis</span>
     <li><span class="dfn-paneled" id="term-for-inline-base-direction" style="color:initial">inline base direction</span>
    </ul>
   <li>
    <a data-link-type="biblio">[CSS21]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-propdef-height" style="color:initial">height</span>
     <li><span class="dfn-paneled" id="term-for-propdef-max-height" style="color:initial">max-height</span>
     <li><span class="dfn-paneled" id="term-for-propdef-width" style="color:initial">width</span>
    </ul>
   <li>
    <a data-link-type="biblio">[CSS3-ALIGN]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-propdef-column-gap" style="color:initial">column-gap</span>
     <li><span class="dfn-paneled" id="term-for-valdef-row-gap-normal" style="color:initial">normal</span>
    </ul>
   <li>
    <a data-link-type="biblio">[CSS3-BREAK]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-propdef-break-after" style="color:initial">break-after</span>
     <li><span class="dfn-paneled" id="term-for-propdef-break-before" style="color:initial">break-before</span>
     <li><span class="dfn-paneled" id="term-for-propdef-break-inside" style="color:initial">break-inside</span>
     <li><span class="dfn-paneled" id="term-for-propdef-orphans" style="color:initial">orphans</span>
    </ul>
  </ul>
  <h2 class="no-num no-ref heading settled" id="references"><span class="content">References</span><a class="self-link" href="#references"></a></h2>
  <h3 class="no-num no-ref heading settled" id="normative"><span class="content">Normative References</span><a class="self-link" href="#normative"></a></h3>
  <dl>
   <dt id="biblio-css-backgrounds-3">[CSS-BACKGROUNDS-3]
   <dd>Bert Bos; Elika Etemad; Brad Kemper. <a href="https://www.w3.org/TR/css-backgrounds-3/">CSS Backgrounds and Borders Module Level 3</a>. 17 October 2017. CR. URL: <a href="https://www.w3.org/TR/css-backgrounds-3/">https://www.w3.org/TR/css-backgrounds-3/</a>
   <dt id="biblio-css-break-4">[CSS-BREAK-4]
   <dd>Rossen Atanassov; Elika Etemad. <a href="https://www.w3.org/TR/css-break-4/">CSS Fragmentation Module Level 4</a>. 18 December 2018. WD. URL: <a href="https://www.w3.org/TR/css-break-4/">https://www.w3.org/TR/css-break-4/</a>
   <dt id="biblio-css-color-3">[CSS-COLOR-3]
   <dd>Tantek Çelik; Chris Lilley; David Baron. <a href="https://www.w3.org/TR/css-color-3/">CSS Color Module Level 3</a>. 19 June 2018. REC. URL: <a href="https://www.w3.org/TR/css-color-3/">https://www.w3.org/TR/css-color-3/</a>
   <dt id="biblio-css-display-3">[CSS-DISPLAY-3]
   <dd>Tab Atkins Jr.; Elika Etemad. <a href="https://www.w3.org/TR/css-display-3/">CSS Display Module Level 3</a>. 28 August 2018. CR. URL: <a href="https://www.w3.org/TR/css-display-3/">https://www.w3.org/TR/css-display-3/</a>
   <dt id="biblio-css-grid-1">[CSS-GRID-1]
   <dd>Tab Atkins Jr.; Elika Etemad; Rossen Atanassov. <a href="https://www.w3.org/TR/css-grid-1/">CSS Grid Layout Module Level 1</a>. 14 December 2017. CR. URL: <a href="https://www.w3.org/TR/css-grid-1/">https://www.w3.org/TR/css-grid-1/</a>
   <dt id="biblio-css-overflow-3">[CSS-OVERFLOW-3]
   <dd>David Baron; Elika Etemad; Florian Rivoal. <a href="https://www.w3.org/TR/css-overflow-3/">CSS Overflow Module Level 3</a>. 31 July 2018. WD. URL: <a href="https://www.w3.org/TR/css-overflow-3/">https://www.w3.org/TR/css-overflow-3/</a>
   <dt id="biblio-css-position-3">[CSS-POSITION-3]
   <dd>Rossen Atanassov; Arron Eicholz. <a href="https://www.w3.org/TR/css-position-3/">CSS Positioned Layout Module Level 3</a>. 17 May 2016. WD. URL: <a href="https://www.w3.org/TR/css-position-3/">https://www.w3.org/TR/css-position-3/</a>
   <dt id="biblio-css-tables-3">[CSS-TABLES-3]
   <dd>Greg Whitworth. <a href="https://www.w3.org/TR/css-tables-3/">CSS Table Module Level 3</a>. 7 March 2017. WD. URL: <a href="https://www.w3.org/TR/css-tables-3/">https://www.w3.org/TR/css-tables-3/</a>
   <dt id="biblio-css-values-3">[CSS-VALUES-3]
   <dd>Tab Atkins Jr.; Elika Etemad. <a href="https://www.w3.org/TR/css-values-3/">CSS Values and Units Module Level 3</a>. 31 January 2019. CR. URL: <a href="https://www.w3.org/TR/css-values-3/">https://www.w3.org/TR/css-values-3/</a>
   <dt id="biblio-css-values-4">[CSS-VALUES-4]
   <dd>Tab Atkins Jr.; Elika Etemad. <a href="https://www.w3.org/TR/css-values-4/">CSS Values and Units Module Level 4</a>. 31 January 2019. WD. URL: <a href="https://www.w3.org/TR/css-values-4/">https://www.w3.org/TR/css-values-4/</a>
   <dt id="biblio-css-writing-modes-4">[CSS-WRITING-MODES-4]
   <dd>Elika Etemad; Koji Ishii. <a href="https://www.w3.org/TR/css-writing-modes-4/">CSS Writing Modes Level 4</a>. 24 May 2018. CR. URL: <a href="https://www.w3.org/TR/css-writing-modes-4/">https://www.w3.org/TR/css-writing-modes-4/</a>
   <dt id="biblio-css21">[CSS21]
   <dd>Bert Bos; et al. <a href="https://www.w3.org/TR/CSS2/">Cascading Style Sheets Level 2 Revision 1 (CSS 2.1) Specification</a>. 7 June 2011. REC. URL: <a href="https://www.w3.org/TR/CSS2/">https://www.w3.org/TR/CSS2/</a>
   <dt id="biblio-css3-align">[CSS3-ALIGN]
   <dd>Elika Etemad; Tab Atkins Jr.. <a href="https://www.w3.org/TR/css-align-3/">CSS Box Alignment Module Level 3</a>. 6 December 2018. WD. URL: <a href="https://www.w3.org/TR/css-align-3/">https://www.w3.org/TR/css-align-3/</a>
   <dt id="biblio-css3-break">[CSS3-BREAK]
   <dd>Rossen Atanassov; Elika Etemad. <a href="https://www.w3.org/TR/css-break-3/">CSS Fragmentation Module Level 3</a>. 4 December 2018. CR. URL: <a href="https://www.w3.org/TR/css-break-3/">https://www.w3.org/TR/css-break-3/</a>
   <dt id="biblio-rfc2119">[RFC2119]
   <dd>S. Bradner. <a href="https://tools.ietf.org/html/rfc2119">Key words for use in RFCs to Indicate Requirement Levels</a>. March 1997. Best Current Practice. URL: <a href="https://tools.ietf.org/html/rfc2119">https://tools.ietf.org/html/rfc2119</a>
  </dl>
  <h3 class="no-num no-ref heading settled" id="informative"><span class="content">Informative References</span><a class="self-link" href="#informative"></a></h3>
  <dl>
   <dt id="biblio-css3-sizing">[CSS3-SIZING]
   <dd>Tab Atkins Jr.; Elika Etemad. <a href="https://www.w3.org/TR/css-sizing-3/">CSS Intrinsic &amp; Extrinsic Sizing Module Level 3</a>. 22 May 2019. WD. URL: <a href="https://www.w3.org/TR/css-sizing-3/">https://www.w3.org/TR/css-sizing-3/</a>
   <dt id="biblio-css3box">[CSS3BOX]
   <dd>Elika Etemad. <a href="https://www.w3.org/TR/css-box-3/">CSS Box Model Module Level 3</a>. 18 December 2018. WD. URL: <a href="https://www.w3.org/TR/css-box-3/">https://www.w3.org/TR/css-box-3/</a>
  </dl>
  <h2 class="no-num no-ref heading settled" id="property-index"><span class="content">Property Index</span><a class="self-link" href="#property-index"></a></h2>
  <div class="big-element-wrapper">
   <table class="index">
    <thead>
     <tr>
      <th scope="col">Name
      <th scope="col">Value
      <th scope="col">Initial
      <th scope="col">Applies to
      <th scope="col">Inh.
      <th scope="col">%ages
      <th scope="col">Ani­mat­able
      <th scope="col">Anim­ation type
      <th scope="col">Canonical order
      <th scope="col">Com­puted value
    <tbody>
     <tr>
      <th scope="row"><a class="css" data-link-type="property" href="#propdef-column-count" id="ref-for-propdef-column-count①④">column-count</a>
      <td>auto | &lt;integer>
      <td>auto
      <td>block containers except table wrapper boxes
      <td>no
      <td>N/A
      <td>by computed value
      <td>
      <td>per grammar
      <td>specified value
     <tr>
      <th scope="row"><a class="css" data-link-type="property" href="#propdef-column-fill" id="ref-for-propdef-column-fill⑤">column-fill</a>
      <td>auto | balance | balance-all
      <td>balance
      <td>multicol containers
      <td>no
      <td>N/A
      <td>
      <td>discrete
      <td>per grammar
      <td>specified keyword
     <tr>
      <th scope="row"><a class="css" data-link-type="property" href="#propdef-column-rule" id="ref-for-propdef-column-rule⑤">column-rule</a>
      <td>&lt;'column-rule-width'> || &lt;'column-rule-style'> || &lt;'column-rule-color'>
      <td>see individual properties
      <td>see individual properties
      <td>see individual properties
      <td>see individual properties
      <td>
      <td>see individual properties
      <td>per grammar
      <td>see individual properties
     <tr>
      <th scope="row"><a class="css" data-link-type="property" href="#propdef-column-rule-color" id="ref-for-propdef-column-rule-color③">column-rule-color</a>
      <td>&lt;color>
      <td>currentcolor
      <td>multicol containers
      <td>no
      <td>N/A
      <td>
      <td>by computed value type
      <td>per grammar
      <td>computed color
     <tr>
      <th scope="row"><a class="css" data-link-type="property" href="#propdef-column-rule-style" id="ref-for-propdef-column-rule-style④">column-rule-style</a>
      <td>&lt;line-style>
      <td>none
      <td>multicol containers
      <td>no
      <td>N/A
      <td>
      <td>discrete
      <td>per grammar
      <td>specified keyword
     <tr>
      <th scope="row"><a class="css" data-link-type="property" href="#propdef-column-rule-width" id="ref-for-propdef-column-rule-width⑤">column-rule-width</a>
      <td>&lt;line-width>
      <td>medium
      <td>multicol containers
      <td>no
      <td>N/A
      <td>
      <td>by computed value type
      <td>per grammar
      <td>absolute length; 0 if the column rule style is none or hidden
     <tr>
      <th scope="row"><a class="css" data-link-type="property" href="#propdef-column-span" id="ref-for-propdef-column-span⑧">column-span</a>
      <td>none | all
      <td>none
      <td>in-flow block-level elements
      <td>no
      <td>N/A
      <td>
      <td>discrete
      <td>per grammar
      <td>specified keyword
     <tr>
      <th scope="row"><a class="css" data-link-type="property" href="#propdef-column-width" id="ref-for-propdef-column-width①⑤">column-width</a>
      <td>auto | &lt;length>
      <td>auto
      <td>block containers except table wrapper boxes
      <td>no
      <td>N/A
      <td>
      <td>by computed value type
      <td>per grammar
      <td>the keyword auto or an absolute length
     <tr>
      <th scope="row"><a class="css" data-link-type="property" href="#propdef-columns" id="ref-for-propdef-columns⑤">columns</a>
      <td>&lt;'column-width'> || &lt;'column-count'>
      <td>see individual properties
      <td>see individual properties
      <td>see individual properties
      <td>see individual properties
      <td>
      <td>see individual properties
      <td>per grammar
      <td>see individual properties
   </table>
  </div>
  <h2 class="no-num no-ref heading settled" id="issues-index"><span class="content">Issues Index</span><a class="self-link" href="#issues-index"></a></h2>
  <div style="counter-reset:issue">
   <div class="issue"> We need to define the behavior of <span class="css">column-fill</span> in continuous contexts. A previous resolution (<a href="https://github.com/w3c/csswg-drafts/issues/3224#issuecomment-468089503">3224</a>) defined that the property should only be consulted if the length of columns was constrained in the block dimension. This was reverted in (<a href="https://github.com/w3c/csswg-drafts/issues/4036#issuecomment-531646703">4036</a>) pending further discussion.<a href="#issue-3ed47ce8"> ↵ </a></div>
  </div>
  <aside class="dfn-panel" data-for="multi-column-layout">
   <b><a href="#multi-column-layout">#multi-column-layout</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-multi-column-layout">2. 
The Multi-Column Model</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="multi-column-container">
   <b><a href="#multi-column-container">#multi-column-container</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-multi-column-container">1. 
Introduction</a> <a href="#ref-for-multi-column-container①">(2)</a>
    <li><a href="#ref-for-multi-column-container②">2. 
The Multi-Column Model</a> <a href="#ref-for-multi-column-container③">(2)</a> <a href="#ref-for-multi-column-container④">(3)</a> <a href="#ref-for-multi-column-container⑤">(4)</a> <a href="#ref-for-multi-column-container⑥">(5)</a> <a href="#ref-for-multi-column-container⑦">(6)</a>
    <li><a href="#ref-for-multi-column-container⑧">3.2. The Number of Columns: the column-count property</a>
    <li><a href="#ref-for-multi-column-container⑨">4. Column Gaps and Rules</a> <a href="#ref-for-multi-column-container①⓪">(2)</a> <a href="#ref-for-multi-column-container①①">(3)</a> <a href="#ref-for-multi-column-container①②">(4)</a> <a href="#ref-for-multi-column-container①③">(5)</a> <a href="#ref-for-multi-column-container①④">(6)</a>
    <li><a href="#ref-for-multi-column-container①⑤">6.1. Spanning An Element Across Columns: the column-span property</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="column-box">
   <b><a href="#column-box">#column-box</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-column-box">2. 
The Multi-Column Model</a> <a href="#ref-for-column-box①">(2)</a> <a href="#ref-for-column-box②">(3)</a> <a href="#ref-for-column-box③">(4)</a> <a href="#ref-for-column-box④">(5)</a> <a href="#ref-for-column-box⑤">(6)</a>
    <li><a href="#ref-for-column-box⑥">8.1. 
Overflow Inside Multicol Containers</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="multi-column-line">
   <b><a href="#multi-column-line">#multi-column-line</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-multi-column-line">2. 
The Multi-Column Model</a> <a href="#ref-for-multi-column-line①">(2)</a> <a href="#ref-for-multi-column-line②">(3)</a> <a href="#ref-for-multi-column-line③">(4)</a>
    <li><a href="#ref-for-multi-column-line④">6.1. Spanning An Element Across Columns: the column-span property</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="column-gap">
   <b><a href="#column-gap">#column-gap</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-column-gap">1. 
Introduction</a>
    <li><a href="#ref-for-column-gap①">4. Column Gaps and Rules</a>
    <li><a href="#ref-for-column-gap②">4.5. Column Rule Shorthand: the column-rule property</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="column-rule">
   <b><a href="#column-rule">#column-rule</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-column-rule">1. 
Introduction</a>
    <li><a href="#ref-for-column-rule①">4. Column Gaps and Rules</a> <a href="#ref-for-column-rule②">(2)</a> <a href="#ref-for-column-rule③">(3)</a>
    <li><a href="#ref-for-column-rule④">4.2. The Color of Column Rules: the 
column-rule-color property</a>
    <li><a href="#ref-for-column-rule⑤">4.5. Column Rule Shorthand: the column-rule property</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="multi-column-formatting-context">
   <b><a href="#multi-column-formatting-context">#multi-column-formatting-context</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-multi-column-formatting-context">4.1. Gutters Between Columns: the column-gap property</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="propdef-column-width">
   <b><a href="#propdef-column-width">#propdef-column-width</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-column-width">2. 
The Multi-Column Model</a>
    <li><a href="#ref-for-propdef-column-width①">3. 
The Number and Width of Columns</a> <a href="#ref-for-propdef-column-width②">(2)</a>
    <li><a href="#ref-for-propdef-column-width③">3.1. The Inline Size of Columns: the column-width property</a> <a href="#ref-for-propdef-column-width④">(2)</a> <a href="#ref-for-propdef-column-width⑤">(3)</a>
    <li><a href="#ref-for-propdef-column-width⑥">3.2. The Number of Columns: the column-count property</a> <a href="#ref-for-propdef-column-width⑦">(2)</a>
    <li><a href="#ref-for-propdef-column-width⑧">3.3. The column-width and column-count Shorthand: The columns Property</a> <a href="#ref-for-propdef-column-width⑨">(2)</a> <a href="#ref-for-propdef-column-width①⓪">(3)</a>
    <li><a href="#ref-for-propdef-column-width①①">3.4. The Pseudo-algorithm</a> <a href="#ref-for-propdef-column-width①②">(2)</a>
    <li><a href="#ref-for-propdef-column-width①③">Changes from the
Candidate Recommendation (CR) of 12 April 2011.</a> <a href="#ref-for-propdef-column-width①④">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="valdef-column-width-auto">
   <b><a href="#valdef-column-width-auto">#valdef-column-width-auto</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-valdef-column-width-auto">2. 
The Multi-Column Model</a>
    <li><a href="#ref-for-valdef-column-width-auto①">3.1. The Inline Size of Columns: the column-width property</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="propdef-column-count">
   <b><a href="#propdef-column-count">#propdef-column-count</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-column-count">2. 
The Multi-Column Model</a>
    <li><a href="#ref-for-propdef-column-count①">3. 
The Number and Width of Columns</a> <a href="#ref-for-propdef-column-count②">(2)</a>
    <li><a href="#ref-for-propdef-column-count③">3.1. The Inline Size of Columns: the column-width property</a>
    <li><a href="#ref-for-propdef-column-count④">3.2. The Number of Columns: the column-count property</a> <a href="#ref-for-propdef-column-count⑤">(2)</a>
    <li><a href="#ref-for-propdef-column-count⑥">3.3. The column-width and column-count Shorthand: The columns Property</a> <a href="#ref-for-propdef-column-count⑦">(2)</a> <a href="#ref-for-propdef-column-count⑧">(3)</a>
    <li><a href="#ref-for-propdef-column-count⑨">3.4. The Pseudo-algorithm</a> <a href="#ref-for-propdef-column-count①⓪">(2)</a> <a href="#ref-for-propdef-column-count①①">(3)</a>
    <li><a href="#ref-for-propdef-column-count①②">Changes from the
Candidate Recommendation (CR) of 12 April 2011.</a> <a href="#ref-for-propdef-column-count①③">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="propdef-columns">
   <b><a href="#propdef-columns">#propdef-columns</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-columns">1. 
Introduction</a>
    <li><a href="#ref-for-propdef-columns①">3. 
The Number and Width of Columns</a>
    <li><a href="#ref-for-propdef-columns②">3.3. The column-width and column-count Shorthand: The columns Property</a> <a href="#ref-for-propdef-columns③">(2)</a>
    <li><a href="#ref-for-propdef-columns④">Changes from the
Candidate Recommendation (CR) of 12 April 2011.</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="propdef-column-rule-color">
   <b><a href="#propdef-column-rule-color">#propdef-column-rule-color</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-column-rule-color">4.2. The Color of Column Rules: the 
column-rule-color property</a>
    <li><a href="#ref-for-propdef-column-rule-color①">4.5. Column Rule Shorthand: the column-rule property</a> <a href="#ref-for-propdef-column-rule-color②">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="propdef-column-rule-style">
   <b><a href="#propdef-column-rule-style">#propdef-column-rule-style</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-column-rule-style">4.3. The Style Of Column Rules: the column-rule-style property</a> <a href="#ref-for-propdef-column-rule-style①">(2)</a>
    <li><a href="#ref-for-propdef-column-rule-style②">4.5. Column Rule Shorthand: the column-rule property</a> <a href="#ref-for-propdef-column-rule-style③">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="propdef-column-rule-width">
   <b><a href="#propdef-column-rule-width">#propdef-column-rule-width</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-column-rule-width">4.3. The Style Of Column Rules: the column-rule-style property</a>
    <li><a href="#ref-for-propdef-column-rule-width①">4.4. The Width Of Column Rules: the column-rule-width property</a>
    <li><a href="#ref-for-propdef-column-rule-width②">4.5. Column Rule Shorthand: the column-rule property</a> <a href="#ref-for-propdef-column-rule-width③">(2)</a>
    <li><a href="#ref-for-propdef-column-rule-width④">Changes from the
Candidate Recommendation (CR) of 12 April 2011.</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="propdef-column-rule">
   <b><a href="#propdef-column-rule">#propdef-column-rule</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-column-rule">1. 
Introduction</a> <a href="#ref-for-propdef-column-rule①">(2)</a> <a href="#ref-for-propdef-column-rule②">(3)</a> <a href="#ref-for-propdef-column-rule③">(4)</a>
    <li><a href="#ref-for-propdef-column-rule④">4.5. Column Rule Shorthand: the column-rule property</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="propdef-column-span">
   <b><a href="#propdef-column-span">#propdef-column-span</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-column-span">1. 
Introduction</a>
    <li><a href="#ref-for-propdef-column-span①">6. 
Spanning Columns</a>
    <li><a href="#ref-for-propdef-column-span②">6.1. Spanning An Element Across Columns: the column-span property</a> <a href="#ref-for-propdef-column-span③">(2)</a> <a href="#ref-for-propdef-column-span④">(3)</a> <a href="#ref-for-propdef-column-span⑤">(4)</a> <a href="#ref-for-propdef-column-span⑥">(5)</a>
    <li><a href="#ref-for-propdef-column-span⑦">Changes from the
Candidate Recommendation (CR) of 12 April 2011.</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="valdef-column-span-none">
   <b><a href="#valdef-column-span-none">#valdef-column-span-none</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-valdef-column-span-none">6.1. Spanning An Element Across Columns: the column-span property</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="valdef-column-span-all">
   <b><a href="#valdef-column-span-all">#valdef-column-span-all</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-valdef-column-span-all">6.1. Spanning An Element Across Columns: the column-span property</a> <a href="#ref-for-valdef-column-span-all①">(2)</a> <a href="#ref-for-valdef-column-span-all②">(3)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="spanner">
   <b><a href="#spanner">#spanner</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-spanner">2. 
The Multi-Column Model</a> <a href="#ref-for-spanner①">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="propdef-column-fill">
   <b><a href="#propdef-column-fill">#propdef-column-fill</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-column-fill">1. 
Introduction</a>
    <li><a href="#ref-for-propdef-column-fill①">7.1. Column Balancing: the column-fill property</a>
    <li><a href="#ref-for-propdef-column-fill②">Changes from the
Candidate Recommendation (CR) of 12 April 2011.</a> <a href="#ref-for-propdef-column-fill③">(2)</a> <a href="#ref-for-propdef-column-fill④">(3)</a>
   </ul>
  </aside>
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